共查询到20条相似文献，搜索用时 15 毫秒
1.
2.
Host plant resistance can effectively manage Russian wheat aphid (Diuraphis noxia) Kurdjumov (Homoptera: Aphididae) in areas where it is an economically important pest of wheat. However, biotypes of D. noxia virulent on wheat containing resistance gene Dn4 have been reported in both the United States and South Africa. Thirty wheat genotypes, including susceptible Yuma, resistant CItr2401, as well as 25 genotypes containing Dn4 and three genotypes containing Dny were planted under greenhouse conditions in Bethlehem, South Africa, and screened with D. noxia biotype RWASA3. RWASA3 caused susceptible damage symptoms in MTRWA92‐145, Ankor, Halt, Bond CL, 18FAWWON‐SA 262, Prowers99, 18FAWWON‐SA 264, Hatcher, Yumar, Corwa and Thunder CL all reported to contain the Dn4 resistance gene. Genotypes PI586956, Stanton and 18FAWWON‐SA 257, containing the Dny‐resistance gene were susceptible to RWASA3. Similarly, coinciding development of virulence to resistance genes Dn4 and Dny was reported in the United States. However, in this study, 13 Dn4‐containing genotypes showed moderate resistance when screened with RWASA3 alluding to a more complex biotype‐gene‐interaction. These findings could indicate that Dn4 and Dny may be related and possibly share a similar or common resistance factor. Further studies will be aimed at explaining these results investigating the possibility of an allelic cluster or series for Dn4, possibly including Dny. 相似文献
3.
Comfort S. Yusuf Ramesh Chand Vinod K. Mishra Arun K. Joshi 《Journal of Phytopathology》2016,164(11-12):896-903
Spot blotch (causative pathogen Bipolaris sorokiniana (Sacc.) Shoem) is a common disease of wheat in the Eastern Gangetic Plains region of India. The association of leaf malondialdehyde and lignin contents with the severity of spot blotch disease was studied using a correlation analysis based on a population of recombinant inbred lines bred from the cross cvs. Yangmai 6 (resistant) × Sonalika (susceptible). The material was field‐tested over two consecutive years and inoculated artificially with a highly virulent strain of the pathogen. Disease severity was assessed at three growth stages around and after anthesis. Leaf lignin content tended to be higher in the more resistant RILs, while the opposite was the case for leaf malondialdehyde content. Lesion size showed a positive correlation with disease severity and leaf malondialdehyde content, while disease severity and leaf lignin content were negatively correlated with one another, as were leaf malondialdehyde and leaf lignin content. Leaf malondialdehyde and/or leaf lignin content could be informative as markers for selection for higher levels of resistance against spot blotch in wheat. 相似文献
4.
Kaitao Lai Michał T. Lorenc Hong Ching Lee Paul J. Berkman Philipp Emanuel Bayer Paul Visendi Pradeep Ruperao Timothy L. Fitzgerald Manuel Zander Chon‐Kit Kenneth Chan Sahana Manoli Jiri Stiller Jacqueline Batley David Edwards 《Plant biotechnology journal》2015,13(1):97-104
Despite being a major international crop, our understanding of the wheat genome is relatively poor due to its large size and complexity. To gain a greater understanding of wheat genome diversity, we have identified single nucleotide polymorphisms between 16 Australian bread wheat varieties. Whole‐genome shotgun Illumina paired read sequence data were mapped to the draft assemblies of chromosomes 7A, 7B and 7D to identify more than 4 million intervarietal SNPs. SNP density varied between the three genomes, with much greater density observed on the A and B genomes than the D genome. This variation may be a result of substantial gene flow from the tetraploid Triticum turgidum, which possesses A and B genomes, during early co‐cultivation of tetraploid and hexaploid wheat. In addition, we examined SNP density variation along the chromosome syntenic builds and identified genes in low‐density regions which may have been selected during domestication and breeding. This study highlights the impact of evolution and breeding on the bread wheat genome and provides a substantial resource for trait association and crop improvement. All SNP data are publically available on a generic genome browser GBrowse at www.wheatgenome.info . 相似文献
5.
Mark O. Winfield Alexandra M. Allen Paul A. Wilkinson Amanda J. Burridge Gary L.A. Barker Jane Coghill Christy Waterfall Luzie U. Wingen Simon Griffiths Keith J. Edwards 《Plant biotechnology journal》2018,16(1):165-175
The importance of wheat as a food crop makes it a major target for agricultural improvements. As one of the most widely grown cereal grains, together with maize and rice, wheat is the leading provider of calories in the global diet, constituting 29% of global cereal production in 2015. In the last few decades, however, yields have plateaued, suggesting that the green revolution, at least for wheat, might have run its course and that new sources of genetic variation are urgently required. The overall aim of our work was to identify novel variation that may then be used to enable the breeding process. As landraces are a potential source of such diversity, here we have characterized the A.E. Watkins Collection alongside a collection of elite accessions using two complementary high‐density and high‐throughput genotyping platforms. While our results show the importance of using the appropriate SNP collection to compare diverse accessions, they also show that the Watkins Collection contains a substantial amount of novel genetic diversity which has either not been captured in current breeding programmes or which has been lost through previous selection pressures. As a consequence of our analysis, we have identified a number of accessions which carry an array of novel alleles along with a number of interesting chromosome rearrangements which confirm the variable nature of the wheat genome. 相似文献
6.
Wei Cheng Xiu‐Shi Song He‐Ping Li Le‐Hui Cao Ke Sun Xiao‐Li Qiu Yu‐Bin Xu Peng Yang Tao Huang Jing‐Bo Zhang Bo Qu Yu‐Cai Liao 《Plant biotechnology journal》2015,13(9):1335-1345
Fusarium head blight (FHB) and Fusarium seedling blight (FSB) of wheat, caused by Fusarium pathogens, are devastating diseases worldwide. We report the expression of RNA interference (RNAi) sequences derived from an essential Fusarium graminearum (Fg) virulence gene, chitin synthase (Chs) 3b, as a method to enhance resistance of wheat plants to fungal pathogens. Deletion of Chs3b was lethal to Fg; disruption of the other Chs gene family members generated knockout mutants with diverse impacts on Fg. Comparative expression analyses revealed that among the Chs gene family members, Chs3b had the highest expression levels during Fg colonization of wheat. Three hairpin RNAi constructs corresponding to the different regions of Chs3b were found to silence Chs3b in transgenic Fg strains. Co‐expression of these three RNAi constructs in two independent elite wheat cultivar transgenic lines conferred high levels of stable, consistent resistance (combined type I and II resistance) to both FHB and FSB throughout the T3 to T5 generations. Confocal microscopy revealed profoundly restricted mycelia in Fg‐infected transgenic wheat plants. Presence of the three specific short interfering RNAs in transgenic wheat plants was confirmed by Northern blotting, and these RNAs efficiently down‐regulated Chs3b in the colonizing Fusarium pathogens on wheat seedlings and spikes. Our results demonstrate that host‐induced gene silencing of an essential fungal chitin synthase gene is an effective strategy for enhancing resistance in crop plants under field test conditions. 相似文献
7.
Mariko Nonogaki Khadidiatou Sall Eiji Nambara Hiroyuki Nonogaki 《The Plant journal : for cell and molecular biology》2014,78(3):527-539
Abscisic acid is an essential hormone for seed dormancy. Our previous study using the plant gene switch system, a chemically induced gene expression system, demonstrated that induction of 9‐cis‐epoxycarotenoid dioxygenase (NCED), a rate‐limiting ABA biosynthesis gene, was sufficient to suppress germination in imbibed Arabidopsis seeds. Here, we report development of an efficient experimental system that causes amplification of NCED expression during seed maturation. The system was created with a Triticum aestivum promoter containing ABA responsive elements (ABREs) and a Sorghum bicolor NCED to cause ABA‐stimulated ABA biosynthesis and signaling, through a positive feedback mechanism. The chimeric gene pABRE:NCED enhanced NCED and ABF (ABRE‐binding factor) expression in Arabidopsis Columbia‐0 seeds, which caused 9‐ to 73‐fold increases in ABA levels. The pABRE:NCED seeds exhibited unusually deep dormancy which lasted for more than 3 months. Interestingly, the amplified ABA pathways also caused enhanced expression of Arabidopsis NCED5, revealing the presence of positive feedback in the native system. These results demonstrated the robustness of positive feedback mechanisms and the significance of NCED expression, or single metabolic change, during seed maturation. The pABRE:NCED system provides an excellent experimental system producing dormant and non‐dormant seeds of the same maternal origin, which differ only in zygotic ABA. The pABRE:NCED seeds contain a GFP marker which enables seed sorting between transgenic and null segregants and are ideal for comparative analysis. In addition to its utility in basic research, the system can also be applied to prevention of pre‐harvest sprouting during crop production, and therefore contributes to translational biology. 相似文献
8.
Abdulqader Jighly Reem Joukhadar Deepmala Sehgal Sukhwinder Singh Francis C. Ogbonnaya Hans D. Daetwyler 《The Plant journal : for cell and molecular biology》2019,100(4):801-812
Sequence elimination is one of the main mechanisms that increases the divergence among homoeologous chromosomes after allopolyploidization to enhance the stability of recently established lineages, but it can cause a loss of some economically important genes. Synthetic hexaploid wheat (SHW) is an important source of genetic variation to the natural hexaploid wheat (NHW) genepool that has low genetic diversity. Here, we investigated the change between SHW and NHW genomes by utilizing a large germplasm set of primary synthetics and synthetic derivatives. Reproducible segment elimination (RSE) was declared if a large chromosomal chunk (>5 cM) produced no aligned reads in more than five SHWs. RSE in five genomic regions was the major source of variation between SHW and NHW. One RSE eliminated almost the complete short arm of chromosome 1B, which contains major genes for flour quality, disease resistance and different enzymes. The occurrence of RSE was highly dependent on the choice of diploid and tetraploid parental lines, their ancestral subpopulation and admixture, e.g. SHWs derived from Triticum dicoccon or from one of two Aegilops tauschii subpopulations were almost free of RSE, while highly admixed parents had higher RSE rates. The rate of RSE in synthetic derivatives was almost double that in primary synthetics. Genome‐wide association analysis detected four loci with minor effects on the occurrence of RSE, indicating that both parental lines and genetic factors were affecting the occurrence of RSE. Therefore, pre‐pre‐breeding strategies should be applied before introducing SHW into pre‐breeding programs to ensure genomic stability and avoid undesirable gene loss. 相似文献
9.
Juan Manuel Debernardi Julian R. Greenwood E. Jean Finnegan Judy Jernstedt Jorge Dubcovsky 《The Plant journal : for cell and molecular biology》2020,101(1):171-187
The spikelet is the basic unit of the grass inflorescence. In tetraploid (Triticum turgidum) and hexaploid wheat (Triticum aestivum), the spikelet is a short indeterminate branch with two proximal sterile bracts (glumes) followed by a variable number of florets, each including a bract (lemma) with an axillary flower. Varying levels of miR172 and/or its target gene Q (AP2L5) result in gradual transitions of glumes to lemmas, and vice versa. Here, we show that AP2L5 and its related paralog AP2L2 play critical and redundant roles in the specification of axillary floral meristems and lemma identity. AP2L2, also targeted by miR172, displayed similar expression profiles to AP2L5 during spikelet development. Loss‐of‐function mutants in both homeologs of AP2L2 (henceforth ap2l2) developed normal spikelets, but ap2l2 ap2l5 double mutants generated spikelets with multiple empty bracts before transitioning to florets. The coordinated nature of these changes suggest an early role of these genes in floret development. Moreover, the flowers of ap2l2 ap2l5 mutants showed organ defects in paleas and lodicules, including the homeotic conversion of lodicules into carpels. Mutations in the miR172 target site of AP2L2 were associated with reduced plant height, more compact spikes, promotion of lemma‐like characters in glumes and smaller lodicules. Taken together, our results show that the balance in the expression of miR172 and AP2‐like genes is crucial for the correct development of spikelets and florets, and that this balance has been altered during the process of wheat and barley (Hordeum vulgare) domestication. The manipulation of this regulatory module provides an opportunity to modify spikelet architecture and improve grain yield. 相似文献
10.
Hong Liu Huifang Li Chenyang Hao Ke Wang Yamei Wang Lin Qin Diaoguo An Tian Li Xueyong Zhang 《Plant biotechnology journal》2020,18(5):1330-1342
Kernel size is an important trait determining cereal yields. In this study, we cloned and characterized TaDA1, a conserved negative regulator of kernel size in wheat (Triticum aestivum). The overexpression of TaDA1 decreased the size and weight of wheat kernels, while its down‐regulation using RNA interference (RNAi) had the opposite effect. Three TaDA1‐A haplotypes were identified in Chinese wheat core collections, and a haplotype association analysis showed that TaDA1‐A‐HapI was significantly correlated with the production of larger kernels and higher kernel weights in modern Chinese cultivars. The haplotype effect resulted from a difference in TaDA1‐A expression levels between genotypes, with TaDA1‐A‐HapI resulting in lower TaDA1‐A expression levels. This favourable haplotype was found having been positively selected during wheat breeding over the last century. Furthermore, we demonstrated that TaDA1‐A physically interacts with TaGW2‐B. The additive effects of TaDA1‐A and TaGW2‐B on kernel weight were confirmed not only by the phenotypic enhancement arising from the simultaneous down‐regulation of TaDA1 and TaGW2 expression, but also by the combinational haplotype effects estimated from multi‐environment field data from 348 wheat cultivars. A comparative proteome analysis of developing transgenic and wild‐type grains indicated that TaDA1 and TaGW2 are involved in partially overlapping but relatively independent protein regulatory networks. Thus, we have identified an important gene controlling kernel size in wheat and determined its interaction with other genes regulating kernel weight, which could have beneficial applications in wheat breeding. 相似文献
11.
TBC(Tre-2/Bub2/Cdc16)是真核生物中普遍存在的一种由200个氨基酸残基组成的保守性蛋白质结构域,含有该结构域的蛋白质被称为TBC蛋白。TBC蛋白具有GTPase激活活性,可促进小G蛋白Rab-GTP水解为Rab-GDP,从而参与特异的胞内转运过程。在哺乳动物中,部分TBC蛋白具有十分重要的作用,其功能异常与人类疾病的发生发展密切相关。本文主要介绍了哺乳动物TBC蛋白的结构和功能,以及近年来TBC蛋白在人类疾病发生发展中的作用,以期为深入解析TBC蛋白的致病机制提供参考。 相似文献
12.
Baochun Li Frédéric Choulet Yanfang Heng Weiwei Hao Etienne Paux Zhao Liu Wei Yue Weiwei Jin Catherine Feuillet Xueyong Zhang 《The Plant journal : for cell and molecular biology》2013,73(6):952-965
The physical map of the hexaploid wheat chromosome 3B was screened using centromeric DNA probes. A 1.1‐Mb region showing the highest number of positive bacterial artificial chromosome (BAC) clones was fully sequenced and annotated, revealing that 96% of the DNA consisted of transposable elements, mainly long terminal repeat (LTR) retrotransposons (88%). Estimation of the insertion time of the transposable elements revealed that CRW (also called Cereba) and Quinta are the youngest elements at the centromeres of common wheat (Triticum spp.) and its diploid ancestors, with Quinta being younger than CRW in both diploid and hexaploid wheats. Chromatin immunoprecipitation experiments revealed that both CRW and Quinta families are targeted by the centromere‐specific histone H3 variant CENH3. Immuno colocalization of retroelements and CENH3 antibody indicated that a higher proportion of Quinta than CRWs was associated with CENH3, although CRWs were more abundant. Long arrays of satellite repeats were also identified in the wheat centromere regions, but they lost the ability to bind with CENH3. In addition to transposons, two functional genes and one pseudogene were identified. The gene density in the centromere appeared to be between three and four times lower than the average gene density of chromosome 3B. Comparisons with related grasses also indicated a loss of microcollinearity in this region. Finally, comparison of centromeric sequences of Aegilops tauschii (DD), Triticum boeoticum (AA) and hexaploid wheat revealed that the centromeres in both the polyploids and diploids are still undergoing dynamic changes, and that the new CRWs and Quintas may have undertaken the core role in kinetochore formation. 相似文献
13.
Dongfang Ma Fei Peng Zhengwu Fang Kaixiang Chao Jinxue Jing Changqing Zhang 《Journal of Phytopathology》2015,163(2):98-104
Stripe rust, caused by Puccinia striiformis f.sp. tritici (Pst), is one of the most widespread and destructive diseases of wheat worldwide. Resistance breeding is constantly pursued for decades to tackle the variations of prevalent Pst races. Zhongliang 12 has strong resistance to abiotic stresses, wide adaptability, higher resistance to stripe rust and excellent biological characteristics. To identify the resistance gene(s) against stripe rust, Zhongliang 12 was crossed with stripe rust susceptible genotype Mingxian 169, and F1, F2, F2 : 3 and BC1 progenies were tested with Chinese Pst race CYR30 and CYR31 in seedling stage in greenhouse. Zhongliang 12 possessed different dominant genes for resistance to each race. Linkage maps were constructed with four simple sequence repeats (SSRs) markers, Xwmc695, Xcfd20, Xbarc121 and Xbarc49, for the gene on wheat chromosome 7AL conferring resistance to CYR30 (temporarily designated as Yrzhong12‐1) with genetic distance ranging from 3.1 to 10.8 cM and four SSR markers, Xpsp3003, Xcfd2129, Xwmc673 and Xwmc51, for the gene on wheat chromosome 1AL conferring resistance to CYR31 (temporarily designated as Yrzhong12‐2) with genetic distance ranging from 3.9 cM to 9.3 cM. The molecular markers closely linked to each gene should be useful in marker‐assisted selection in breeding programmes for against stripe rust. 相似文献
14.
Meng Ma Qian Wang Zhanjie Li Huihui Cheng Zhaojie Li Xiangli Liu Weining Song Rudi Appels Huixian Zhao 《The Plant journal : for cell and molecular biology》2015,83(2):312-325
Several studies have described quantitative trait loci (QTL) for seed size in wheat, but the relevant genes and molecular mechanisms remain largely unknown. Here we report the functional characterization of the wheat TaCYP78A3 gene and its effect on seed size. TaCYP78A3 encoded wheat cytochrome P450 CYP78A3, and was specifically expressed in wheat reproductive organs. TaCYP78A3 activity was positively correlated with the final seed size. Its silencing caused a reduction of cell number in the seed coat, resulting in an 11% decrease in wheat seed size, whereas TaCYP78A3 over‐expression induced production of more cells in the seed coat, leading to an 11–48% increase in Arabidopsis seed size. In addition, the cell number in the final seed coat was determined by the TaCYP78A3 expression level, which affected the extent of integument cell proliferation in the developing ovule and seed. Unfortunately, TaCYP78A3 over‐expression in Arabidopsis caused a reduced seed set due to an ovule developmental defect. Moreover, TaCYP78A3 over‐expression affected embryo development by promoting embryo integument cell proliferation during seed development, which also ultimately affected the final seed size in Arabidopsis. In summary, our results indicated that TaCYP78A3 plays critical roles in influencing seed size by affecting the extent of integument cell proliferation. The present study provides direct evidence that TaCYP78A3 affects seed size in wheat, and contributes to an understanding of the cellular basis of the gene influencing seed development. 相似文献
15.
Meng Wang Jiarui Yuan Lumin Qin Weiming Shi Guangmin Xia Shuwei Liu 《Plant biotechnology journal》2020,18(3):791-804
As one of the largest gene families in plants, the cytochrome P450 monooxygenase genes (CYPs) are involved in diverse biological processes including biotic and abiotic stress response. Moreover, P450 genes are prone to expanding due to gene tandem duplication during evolution, resulting in generations of novel alleles with the neo‐function or enhanced function. Here, the bread wheat (Triticum aestivum) gene TaCYP81D5 was found to lie within a cluster of five tandemly arranged CYP81D genes, although only a single such gene (BdCYP81D1) was present in the equivalent genomic region of the wheat relative Brachypodium distachyon. The imposition of salinity stress could up‐regulate TaCYP81D5, but the effect was abolished in plants treated with an inhibitor of reactive oxygen species synthesis. In SR3, a wheat cultivar with an elevated ROS content, the higher expression and the rapider response to salinity of TaCYP81D5 were related to the chromatin modification. Constitutively expressing TaCYP81D5 enhanced the salinity tolerance both at seedling and reproductive stages of wheat via accelerating ROS scavenging. Moreover, an important component of ROS signal transduction, Zat12, was proven crucial in this process. Though knockout of solely TaCYP81D5 showed no effect on salinity tolerance, knockdown of BdCYP81D1 or all TaCYP81D members in the cluster caused the sensitivity to salt stress. Our results provide the direct evidence that TaCYP81D5 confers salinity tolerance in bread wheat and this gene is prospective for crop improvement. 相似文献
16.
Jian Hou Tian Li Yamei Wang Chenyang Hao Hongxia Liu Xueyong Zhang 《Plant biotechnology journal》2017,15(12):1533-1543
ADP‐glucose pyrophosphorylase, comprising two small subunits and two large subunits, is considered a key enzyme in the endosperm starch synthesis pathway in wheat (Triticum aestivum L.). Two genes, TaAGP‐S1‐7A and TaAGP‐L‐1B, were investigated in this study. Haplotypes of these genes were associated with thousand kernel weight (TKW) in different populations. Mean TKWs of favoured haplotypes were significantly higher than those of nonfavoured ones. Two molecular markers developed to distinguish these haplotypes could be used in molecular breeding. Frequencies of favoured haplotypes were dramatically increased in cultivars released in China after the 1940s. These favoured haplotypes were also positively selected in six major wheat production regions globally. Selection of AGP‐S1 and AGP‐L‐1B in wheat mainly occurred during and after hexaploidization. Strong additive effects of the favoured haplotypes of with other genes for starch synthesis were also detected in different populations. 相似文献
17.
Huyen T.T. Phan Kasia Rybak Eiko Furuki Susan Breen Peter S. Solomon Richard P. Oliver Kar‐Chun Tan 《The Plant journal : for cell and molecular biology》2016,87(4):343-354
Fungal effector–host sensitivity gene interactions play a key role in determining the outcome of septoria nodorum blotch disease (SNB) caused by Parastagonospora nodorum on wheat. The pathosystem is complex and mediated by interaction of multiple fungal necrotrophic effector–host sensitivity gene systems. Three effector sensitivity gene systems are well characterized in this pathosystem; SnToxA–Tsn1, SnTox1–Snn1 and SnTox3–Snn3. We tested a wheat mapping population that segregated for Snn1 and Snn3 with SN15, an aggressive P. nodorum isolate that produces SnToxA, SnTox1 and SnTox3, to study the inheritance of sensitivity to SnTox1 and SnTox3 and disease susceptibility. Interval quantitative trait locus (QTL) mapping showed that the SnTox1–Snn1 interaction was paramount in SNB development on both seedlings and adult plants. No effect of the SnTox3–Snn3 interaction was observed under SN15 infection. The SnTox3–Snn3 interaction was however, detected in a strain of SN15 in which SnTox1 had been deleted (tox1–6). Gene expression analysis indicates increased SnTox3 expression in tox1–6 compared with SN15. This indicates that the failure to detect the SnTox3–Snn3 interaction in SN15 is due – at least in part – to suppressed expression of SnTox3 mediated by SnTox1. Furthermore, infection of the mapping population with a strain deleted in SnToxA, SnTox1 and SnTox3 (toxa13) unmasked a significant SNB QTL on 2DS where the SnTox2 effector sensitivity gene, Snn2, is located. This QTL was not observed in SN15 and tox1–6 infections and thus suggesting that SnToxA and/or SnTox3 were epistatic. Additional QTLs responding to SNB and effectors sensitivity were detected on 2AS1 and 3AL. 相似文献
18.
Severine Hurni Susanne Brunner Daniel Stirnweis Gerhard Herren David Peditto Robert A. McIntosh Beat Keller 《The Plant journal : for cell and molecular biology》2014,79(6):904-913
The powdery mildew resistance gene Pm8 derived from rye is located on a 1BL.1RS chromosome translocation in wheat. However, some wheat lines with this translocation do not show resistance to isolates of the wheat powdery mildew pathogen avirulent to Pm8 due to an unknown genetically dominant suppression mechanism. Here we show that lines with suppressed Pm8 activity contain an intact and expressed Pm8 gene. Therefore, the absence of Pm8 function in certain 1BL.1RS‐containing wheat lines is not the result of gene loss or mutation but is based on suppression. The wheat gene Pm3, an ortholog of rye Pm8, suppressed Pm8‐mediated powdery mildew resistance in lines containing Pm8 in a transient single‐cell expression assay. This result was further confirmed in transgenic lines with combined Pm8 and Pm3 transgenes. Expression analysis revealed that suppression is not the result of gene silencing, either in wheat 1BL.1RS translocation lines carrying Pm8 or in transgenic genotypes with both Pm8 and Pm3 alleles. In addition, a similar abundance of the PM8 and PM3 proteins in single or double homozygous transgenic lines suggested that a post‐translational mechanism is involved in suppression of Pm8. Co‐expression of Pm8 and Pm3 genes in Nicotiana benthamiana leaves followed by co‐immunoprecipitation analysis showed that the two proteins interact. Therefore, the formation of a heteromeric protein complex might result in inefficient or absent signal transmission for the defense reaction. These data provide a molecular explanation for the suppression of resistance genes in certain genetic backgrounds and suggest ways to circumvent it in future plant breeding. 相似文献
19.
Ganesh V. Pusapati Giovanni Luchetti Suzanne R. Pfeffer 《The Journal of biological chemistry》2012,287(50):42129-42137
Rab GTPases are master regulators of membrane trafficking events and template the directionality of protein transport through the secretory and endocytic pathways. Certain Rabs recruit the guanine nucleotide exchange factor (GEF) that activates a subsequent acting Rab protein in a given pathway; this process has been termed a Rab cascade. We show here that the medial Golgi-localized Rab33B GTPase has the potential to link functionally to the late Golgi, Rab6 GTPase, by its capacity for association with Ric1 and Rgp1 proteins. In yeast, Ric1p and Rgp1p form a complex that catalyzes guanine nucleotide exchange by Ypt6p, the Rab6 homolog. Human Ric1 and Rgp1 both bind Rab6A with preference for the GDP-bound conformation, characteristic of a GEF. Nevertheless, both Ric1 and Rgp1 proteins are needed to catalyze nucleotide exchange on Rab6A protein. Ric1 and Rgp1 form a complex, but unlike their yeast counterparts, most of the subunits are not associated, and most of the proteins are cytosolic. Loss of Ric1 or Rgp1 leads to destabilization of Rab6, concomitant with a block in Rab6-dependent retrograde transport of mannose 6-phosphate receptors to the Golgi. The C terminus of Ric1 protein contains a distinct binding site for Rab33B-GTP, supporting the existence of a Rab cascade between the medial and trans Golgi. This study thus identifies a GEF for Rab6A in human cells. 相似文献
20.
Wei Wang Qianli Pan Bin Tian Fei He Yueying Chen Guihua Bai Alina Akhunova Harold N. Trick Eduard Akhunov 《The Plant journal : for cell and molecular biology》2019,100(2):251-264
Grain size and weight are important components of a suite of yield‐related traits in crops. Here, we showed that the CRISPR‐Cas9 gene editing of TaGW7, a homolog of rice OsGW7 encoding a TONNEAU1‐recruiting motif (TRM) protein, affects grain shape and weight in allohexaploid wheat. By editing the TaGW7 homoeologs in the B and D genomes, we showed that mutations in either of the two or both genomes increased the grain width and weight but reduced the grain length. The effect sizes of mutations in the TaGW7 gene homoeologs coincided with the relative levels of their expression in the B and D genomes. The effects of gene editing on grain morphology and weight traits were dosage dependent with the double‐copy mutant showing larger effect than the respective single copy mutants. The TaGW7‐centered gene co‐expression network indicated that this gene is involved in the pathways regulating cell division and organ growth, also confirmed by the cellular co‐localization of TaGW7 with α‐ and β‐tubulin proteins, the building blocks of microtubule arrays. The analyses of exome capture data in tetraploid domesticated and wild emmer, and hexaploid wheat revealed the loss of diversity around TaGW7‐associated with domestication selection, suggesting that TaGW7 is likely to play an important role in the evolution of yield component traits in wheat. Our study showed how integrating CRISPR‐Cas9 system with cross‐species comparison can help to uncover the function of a gene fixed in wheat for allelic variants targeted by domestication selection and select targets for engineering new gene variants for crop improvement. 相似文献