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61.
62.
Umar S Wang Y Morris AP Sellin JH 《American journal of physiology. Gastrointestinal and liver physiology》2007,292(2):G599-G607
Casein kinase I (CKI)-epsilon and GSK-3beta phosphorylate beta-catenin at Ser(45) (beta-cat(45)) and Thr(41)/Ser(37,33) (beta-cat(33,37,41)) residues, thereby facilitating its ubiquitination and proteasomal degradation. We used a Citrobacter rodentium-induced transmissible murine colonic hyperplasia (TMCH) model to determine Ser/Thr phosphorylation and biological function of beta-catenin during crypt hyperproliferation. TMCH was associated with 3-fold and 3.3-fold increases in CKI-epsilon cellular abundance and 2-fold and 1.8-fold increase in its activity at 6 and 12 days after infection, respectively. beta-Catenin coimmunoprecipitated with both cellular and nuclear CKI-epsilon and cellular axin at these time points. Cellular beta-catenin was constitutively phosphorylated at Ser(45) and underwent subcellular redistribution to cytoskeletal and nuclear fractions at days 6 and 12 of TMCH, respectively. beta-cat(33,37,41), however, exhibited only subtle changes in either phosphorylation status or subcellular distribution even after blocking proteasomal degradation in vivo. Interestingly, GSK-3beta underwent increased phosphorylation at Ser(9), leading to 40% and 70% decreases in its activity at these time points, respectively. Coimmunoprecipitation studies exhibited strong association of GSK-3beta with PKC-zeta at either time point. Cellular beta-cat(45) stabilized and, along with unphosphorylated beta-catenin, underwent nuclear translocation, associated with nuclear accumulated Tcf-4 and cAMP response element binding protein binding protein, and was significantly acetylated, leading to increases in DNA binding. Priming of beta-catenin at Ser(45) exists in vivo. However, beta-cat(45) does not necessarily enter the degradation pathway. Impairment in linking beta-cat(45) to subsequent GSK-3beta-mediated phosphorylation and degradation may account for increased steady-state levels of both unphosphorylated as well as Ser(45)-phosphorylated beta-catenin, which may be causally linked to increases in cell census during TMCH. 相似文献
63.
Cytoplasmic localization of the ORF2 protein of hepatitis E virus is dependent on its ability to undergo retrotranslocation from the endoplasmic reticulum 下载免费PDF全文
Hepatitis E virus (HEV) is a positive-strand RNA virus that is prevalent in much of the developing world. ORF2 is the major capsid protein of HEV. Although ORF2 is an N-linked glycoprotein, it is abundantly located in the cytoplasm in addition to having membrane and surface localization. The mechanism by which ORF2 protein obtains access to the cytoplasm is unknown. In this report, we prove that initially all ORF2 protein is present in the endoplasmic reticulum and a fraction of it becomes retrotranslocated to the cytoplasm. The ability of ORF2 to be retrotranslocated is dependent on its glycosylation status and follows the canonical dislocation pathway. However, in contrast to general substrates of the dislocation pathway, retrotranslocated ORF2 protein is not a substrate of the 26S proteasome complex and is readily detectable in the cytoplasm in the absence of any protease inhibitor, suggesting that the retrotranslocated protein is stable in the cytoplasm. This study thus defines the pathway by which ORF2 obtains access to the cytoplasm. 相似文献
64.
The superior performance of F1 hybrids has a significant impact on agricultural productivity. For commercial application, the availability of an efficient
system for obtaining male-sterile lines of crops is an essential prerequisite. Here we have investigated the use of RNA interference
(RNAi) technology to silence a male-specific gene in the model host tobacco. TA29 is expressed exclusively in anthers at the time of microspore development. About 10 out of 13 tobacco lines transformed with
a hairpin RNAi construct containing TA29 sequences were male sterile. Transgenic plants were phenotypically indistinguishable from non-transgenic plants. At the anthesis
stage, pollen grains from transgenic, male-sterile plants were aborted and lysed in comparison to the round and fully developed
pollen in non-transgenic plants. Microscopic analysis of anthers showed selective degradation of tapetum in transgenic plants
with no microspore development. One week after self-pollination, the ovules of non-transgenic plants were double the size
of those in transgenic plants, due to successful self-fertilization. Male sterile transgenic plants set seed normally, when
cross-pollinated with pollen from non-transgenic plants, confirming no adverse effect on the female parts of the flower. These
results show that silencing of male-specific genes by RNAi is potentially a useful tool for generating male-sterile lines
for producing hybrid seed. 相似文献
65.
Tauqeer Ahmad Yasir Sobia Aslam Muhammad Shahid Rizwan Allah Wasaya Muhammad Ateeq Muhammad Naeem Khan Sikander Khan Tanveer Walid Soufan Basharat Ali Allah Ditta Arpna Kumari Ayman EL Sabagh 《Phyton》2022,91(11):2491-2504
In soil biota, higher and enduring concentration of heavy metals like cadmium (Cd) is hazardous and associated
with great loss in growth, yield, and quality parameters of most of the crop plants. Recently, in-situ applications of
eco-friendly stabilizing agents in the form of organic modifications have been utilized to mitigate the adverse
effects of Cd-toxicity. This controlled experiment was laid down to appraise the imprints of various applied
organic amendments namely poultry manure (PM), farmyard manure (FYM), and sugarcane press mud (PS)
to immobilize Cd in polluted soil. Moreover, phytoavailability of Cd in wheat was also accessed under an alkaline
environment. Results revealed that the addition of FYM (5–10 ton ha-1
) in Cd-contaminated soil significantly
increased germination rate, leaf chlorophyll content, plant height, spike length, biological and grain yield amongst
all applied organic amendments. Moreover, the addition of FYM (5–10 ton ha-1
) also reduced the phytoavailability of Cd by 73–85% in the roots, 57–83% in the shoots, and 81–90% in grains of wheat crop. Thus, it is affirmed
that incorporation of FYM (5–10 ton ha-1
) performed better to enhance wheat growth and yield by remediating
Cd. Thus, the application of FYM (5–10 ton ha-1
) reduced the toxicity induced by Cd to plants by declining its
uptake and translocation as compared to all other applied organic amendments to immobilize Cd under sandy
alkaline polluted soil. 相似文献
66.
Mohammed I. Al-Daej Mohamed M. El-Malky Muhammad N. Sattar Adel A. Rezk Muhammad N. Naqqash Jameel M. Al-Khayri 《Phyton》2022,91(9):1905-1922
Rice stem borer (Chilo agamemnon Bles.) is a primary insect pest of rice and is a major limiting factor to rice
production. Breeding for insect-resistant crop varieties has been an economic way of integrated pest management
(IPM) as it offers a viable and ecologically acceptable approach. This study was aimed to evaluate rice genotypes
for their resistance against rice stem borer. Seven parental genotypes with twenty one F1 crosses were evaluated
for genotypic variation in field experiments. Analysis of variance revealed significant differences for the studied
traits in almost all crosses and parents. In addition, the mean squares of parents versus their crosses were signifi-
cant for stem borer resistance and other associated traits. Moreover, both general combining ability (GCA) and
specific combining ability (SCA) variances were highly significant for all characters studied in the F1 generation.
Based on GCA, 4 genotypes (Sakha101, Gz6903-3-4-2-1, Gz9577-4-1-1 and Hassawi) exhibited highly significant
negative values for stem borer resistance (–0.53, –1.06, –0.18 and –0.49, respectively) indicating they are the best
combiners for stem borer resistance. Based on SCA analysis, nine cross combinations showed highly significant
negative effects for stem borer resistance. Similarly, the cross Giza178 Hassawi was the best combination with
significantly highest value for early maturity. In addition, seven crosses showed highly significant negative
SCA for plant height trait. On the other hand, for panicle length, number of primary branches/panicle, panicle
weight and 1000-grain weight, seven, four, eight and six crosses showed highly significant positive SCA, respectively. The result further revealed that the non-additive dominance genetic variance was higher than the additive
variance for all evaluated traits indicating that non-additive genetic variances have a role in their inheritance. The
broad-sense heritability estimates were high for all the studied traits. The stem borer resistance was significantly
correlated with panicle weight and 1000-grain weight, which also showed a highly significant correlation with
grain yield/plant. Thus these traits can be effectively employed in a breeding program to confer resistance against
stem borer infestation in rice. It was further supported by biplot analysis, which clustered these potentially important traits into two quadrants showing their importance in any future breeding program to control stem borer
infestation. This study has contributed valuable information for evaluation of genetic diversity in the local rice
germplasm and its utilization in futuristic rice genetic improvement programs. 相似文献
67.
Dakheel Khulood Hamid Abdul Rahim Raha Al-Obaidi Jameel R. Neela Vasantha Kumari Hun Tan Geok Mat Isa Mohd Noor Razali Nurhanani Yusoff Khatijah 《Biotechnology letters》2022,44(3):513-522
Biotechnology Letters - The degradation activity of two bacteriophages UPMK_1 and UPMK_2 against methicillin-resistant Staphylococcus aureus phages were examined using gel... 相似文献
68.
Bashir Nabiha Ishfaq Mehreen Mazhar Kehkashan Khan Jahangir Sarwar Shahid Ramla 《Molecular biology reports》2022,49(1):487-495
Molecular Biology Reports - Biological treatment of many cancers currently targets membrane bound receptors located on a cell surface. We are in a great to need identify novel membrane proteins... 相似文献
69.
Ricardo S. Ramiro Shahid M. Khan Blandine Franke-Fayard Chris J. Janse Darren J. Obbard Sarah E. Reece 《Proceedings. Biological sciences / The Royal Society》2015,282(1806)
Sexual reproduction is an obligate step in the life cycle of many parasites, including the causative agents of malaria (Plasmodium). Mixed-species infections are common in nature and consequently, interactions between heterospecific gametes occur. Given the importance of managing gene flow across parasite populations, remarkably little is understood about how reproductive isolation between species is maintained. We use the rodent malaria parasites P. berghei and P. yoelii to investigate the ecology of mixed-species mating groups, identify proteins involved in pre-zygotic barriers, and examine their evolution. Specifically, we show that (i) hybridization occurs, but at low frequency; (ii) hybridization reaches high levels when female gametes lack the surface proteins P230 or P48/45, demonstrating that these proteins are key for pre-zygotic reproductive isolation; (iii) asymmetric reproductive interference occurs, where the fertility of P. berghei gametes is reduced in the presence of P. yoelii and (iv) as expected for gamete recognition proteins, strong positive selection acts on a region of P230 and P47 (P48/45 paralogue). P230 and P48/45 are leading candidates for interventions to block malaria transmission. Our results suggest that depending on the viability of hybrids, applying such interventions to populations where mixed-species infections occur could either facilitate or hinder malaria control. 相似文献
70.
Ceyda Coruh Sung Hyun Cho Saima Shahid Qikun Liu Andrzej Wierzbicki Michael J. Axtell 《The Plant cell》2015,27(8):2148-2162
Many plant small RNAs are sequence-specific negative regulators of target mRNAs and/or chromatin. In angiosperms, the two most abundant endogenous small RNA populations are usually 21-nucleotide microRNAs (miRNAs) and 24-nucleotide heterochromatic short interfering RNAs (siRNAs). Heterochromatic siRNAs are derived from repetitive regions and reinforce DNA methylation at targeted loci. The existence and extent of heterochromatic siRNAs in other land plant lineages has been unclear. Using small RNA-sequencing (RNA-seq) of the moss Physcomitrella patens, we identified 1090 loci that produce mostly 23- to 24-nucleotide siRNAs. These loci are mostly in intergenic regions with dense DNA methylation. Accumulation of siRNAs from these loci depends upon P. patens homologs of DICER-LIKE3 (DCL3), RNA-DEPENDENT RNA POLYMERASE2, and the largest subunit of DNA-DEPENDENT RNA POLYMERASE IV, with the largest subunit of a Pol V homolog contributing to expression at a smaller subset of the loci. A MINIMAL DICER-LIKE (mDCL) gene, which lacks the N-terminal helicase domain typical of DCL proteins, is specifically required for 23-nucleotide siRNA accumulation. We conclude that heterochromatic siRNAs, and their biogenesis pathways, are largely identical between angiosperms and P. patens, with the notable exception of the P. patens-specific use of mDCL to produce 23-nucleotide siRNAs. 相似文献