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961.
Quantitative trait loci (QTL) analysis for rice grain width and fine mapping of an identified QTL allele gw-5 in a recombination hotspot region on chromosome 5 总被引:10,自引:0,他引:10 下载免费PDF全文
Rice grain width and shape play a crucial role in determining grain quality and yield. The genetic basis of rice grain width was dissected into six additive quantitative trait loci (QTL) and 11 pairs of epistatic QTL using an F(7) recombinant inbred line (RIL) population derived from a single cross between Asominori (japonica) and IR24 (indica). QTL by environment interactions were evaluated in four environments. Chromosome segment substitution lines (CSSLs) harboring the six additive effect QTL were used to evaluate gene action across eight environments. A major, stable QTL, qGW-5, consistently decreased rice grain width in both the Asominori/IR24 RIL and CSSL populations with the genetic background Asominori. By investigating the distorted segregation of phenotypic values of rice grain width and genotypes of molecular markers in BC(4)F(2) and BC(4)F(3) populations, qGW-5 was dissected into a single recessive gene, gw-5, which controlled both grain width and length-width ratio. gw-5 was narrowed down to a 49.7-kb genomic region with high recombination frequencies on chromosome 5 using 6781 BC(4)F(2) individuals and 10 newly developed simple sequence repeat markers. Our results provide a basis for map-based cloning of the gw-5 gene and for marker-aided gene/QTL pyramiding in rice quality breeding. 相似文献
962.
Chen N Zinchenko AA Yoshikawa Y Araki S Adachi S Yamazoe M Hiraga S Yoshikawa K 《Journal of bacteriology》2008,190(10):3731-3737
Fluorescence microscopic observation of individual T4 DNA molecules revealed that the MukBEF complex (bacterial condensin) and its subunit, the MukB (a member of the SMC [structural maintenance of chromosomes] superfamily) homodimer, of Escherichia coli markedly shrunk large DNA molecules in the presence of hydrolyzable ATP. In contrast, in the presence of ADP or ATP-gammaS, the conformation of DNA was almost not changed. This suggests that the ATPase activity of subunit MukB is essential for shrinking large DNA molecules. Stretching experiments on the shrunken DNA molecules in the presence of ATP and MukBEF indicated a cross-bridging interaction between DNA molecules. 相似文献
963.
964.
Hong-sheng Wu Xiao-ming Yin Dong-yang Liu Ning Ling Wei Bao Rong-rong Ying Yi-yong Zhu Shi-wei Guo Qi-rong Shen 《Plant and Soil》2008,308(1-2):255-266
The impact of fusaric acid (FA) phytotoxin on the physiology of root leaf cells in watermelon seedlings was evaluated. Results revealed that the cell membrane potential treated with FA in 12 h was decreased by 61.9–81.8% compared with untreated controls. FA markedly accelerated the lipid peroxidase activity of watermelon leaves. Malondiadehyde in leaves treated with different concentrations of FA in 24 h was 5.2–11.0 fold as much as control. Phenylalanine ammonia-lyase activity (PAL) in leaves treated with FA was first increased and then decreased. The highest PAL activity was obtained after 6–12 h, which was 7.2–10.5 fold as much as control. Activities of catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) were first increased and then decreased when the seedlings were treated with FA. The highest SOD and POD activities were observed after 12 h and then both declined. The β-1,3-glucanase and chitinase activities in leaves treated with FA were first quickly increased and then declined, the highest activities were found after 12 and 3 h. We concluded that FA strongly inhibited root and leaf cells functions physiologically responsible for fusarium wilt of watermelon. 相似文献
965.
Chengying Ma Chengkun Wang Dingyi Luo Lu Yan Wenxian Yang Ningning Li Ning Gao 《Cell research》2022,(2):176-189
The lateral segregation of membrane constituents into functional microdomains,conceptually known as lipid raft,is a universal organization principle for cellula... 相似文献
966.
967.
Recombinant sortase A (SrtA) was used to immune rabbit, and the inhibitory activity of anti-SrtA serum on Staphylococcus aureus biofilm formation was tested. Biofilm formation was inhibited by anti-SrtA rabbit serum in S. aureus ATCC25923 and two clinical isolated strains. The antiserum was separated into two fractions, and the main component with
the inhibitory activity was demonstrated to be the IgG fraction. Two proteins interact with the IgG fraction were identified
by using an in vitro pull-down assay and were confirmed to be lipase 2 and γ-hemolysin by mass spectrometry. Cross-interaction
between SrtA and lipase 2 was further confirmed by Western blotting. Addition of anti-lipase 2 serum in the culture medium
also showed inhibitory effect against biofilm formation. Together, our study suggests anti-SrtA serum inhibits S. aureus biofilm formation and lipase 2 is one of the targets of anti-SrtA serum in this inhibition process. This is the first study
to demonstrate the roles of antisera against SrtA and lipase 2 in the inhibition of biofilm formation in S. aureus. 相似文献
968.
969.
970.
The gene targeting combined somatic cell nuclear transfer is very useful in agriculture and medicine. Epigenetic modification of DNA by methylation is significant in regulating gene expression during mammalian development. During gene targeting, epigenetic status of donor cell nuclei may be changed in a series of processes, including homologous recombination, cell selection and cloning. We examined DNA methylation of six genes (beta-actin, VEGF, oct4, TERT, H19 and Igf2) and a repetitive sequence art2 in blg(+/-) cell line from beta-lactoglobulin (BLG) gene targeted fetus and the cells used for BLG gene targeting serve as control. The results demonstrated that the widespread changes of DNA methylation were found in blg(+/-) cell line. But the degree of variation was different. DNA methylation of VEGF in blg(+/-) was noticeably decreased. These observations suggest that DNA methylation variations may impact gene expression and finally induce abnormalities and lethality in later developmental stages. 相似文献