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991.
Xiao Y Lan L Yin C Deng X Baker D Zhou JM Tang X 《Molecular plant-microbe interactions : MPMI》2007,20(3):223-234
The Pseudomonas syringae type III secretion system (T3SS) is induced during interaction with the plant or culture in minimal medium (MM). How the bacterium senses these environments to activate the T3SS is poorly understood. Here, we report the identification of a novel two-component system (TCS), RhpRS, that regulates the induction of P. syringae T3SS genes. The rhpR and rhpS genes are organized in an operon with rhpR encoding a putative TCS response regulator and rhpS encoding a putative biphasic sensor kinase. Transposon insertion in rhpS severely reduced the induction of P. syringae T3SS genes in the plant as well as in MM and significantly compromised the pathogenicity on host plants and hypersensitive response-inducing activity on nonhost plants. However, deletion of the rhpRS locus allowed the induction of T3SS genes to the same level as in the wild-type strain and the recovery of pathogenicity upon infiltration into plants. Overexpression of RhpR in the deltarhpRS deletion strain abolished the induction of T3SS genes. However, overexpression of RhpR in the wild-type strain or overexpression of RhpR(D70A), a mutant of the predicted phosphorylation site of RhpR, in the deltarhpRS deletion strain only slightly reduced the induction of T3SS genes. Based on these results, we propose that the phosphorylated RhpR represses the induction of T3SS genes and that RhpS reverses phosphorylation of RhpR under the T3SS-inducing conditions. Epistasis analysis indicated that rhpS and rhpR act upstream of hrpR to regulate T3SS genes. 相似文献
992.
Background
Previous studies have reported frequent stretches of homozygosity in human subjects but have failed to clarify whether these are due to cytogenetic abnormalities or to autozygosity.Methods
Trios which had been typed for closely spaced SNPs spanning the genome were studied. Stretches of extended homozygosity were identified in the child members, as were occasions on which the child had been genotyped as not inheriting one parental allele. The number of times such transmission errors occurred within regions of extended homozygosity was compared with the chance expectation.Results
Transmission errors occurred more rarely in regions of extended homozygosity than would be expected by chance.Discussion
Regions of extended homozygosity are not generally due to cytogenetic abnormalities such as uniparental isodisomy. They reflect the Mendelian inheritance of haplotypes from a common ancestor. This may have implications for mapping disease genes. 相似文献993.
Following the publication of our recent article (Kapp et al., BMC Genomics 2006, 7:231), we (the authors) regrettably found several errors in the published Table 5. This correction article not only describes what makes the published Table 5 incorrect, it also presents the correct Table 5. 相似文献
994.
Widespread RNA segregation in a spiralian embryo 总被引:1,自引:0,他引:1
Asymmetric cell divisions are a crucial mode of cell fate specification in multicellular organisms, but their relative contribution to early embryonic patterning varies among taxa. In the embryo of the mollusc Ilyanassa, most of the early cell divisions are overtly asymmetric. During Ilyanassa early cleavage, mRNAs for several conserved developmental patterning genes localize to interphase centrosomes, and then during division they move to a portion of the cortex that will be inherited by one daughter cell. Here we report an unbiased survey of RNA localization in the Ilyanassa embryo, and examine the overall patterns of centrosomal localization during early development. We find that 3-4% of RNAs are specifically localized to centrosomes during early development, and the remainder are either ubiquitously distributed throughout the cytoplasm or weakly enriched on centrosomes compared with levels in the cytoplasm. We observe centrosomal localization of RNAs in all cells from zygote through the fifth cleavage cycle, and asymmetric RNA segregation in all divisions after the four-cell stage. Remarkably, each specifically localized message is found on centrosomes in a unique subset of cells during early cleavages, and most are found in unique sets of cells at the 24-cell stage. Several specifically localized RNAs are homologous to developmental regulatory proteins in other embryos. These results demonstrate that the mechanisms of localization and segregation are extraordinarily intricate in this system, and suggest that these events are involved in cell fate specification across all lineages in the early Ilyanassa embryo. We propose that greater reliance on segregation of determinants in early cleavage increases constraint on cleavage patterns in molluscs and other spiralian groups. 相似文献
995.
Che FY Zhang X Berezniuk I Callaway M Lim J Fricker LD 《Journal of proteome research》2007,6(12):4667-4676
Sample preparation for neuropeptidomic studies is a critical issue since protein degradation can produce high levels of peptides that obscure the endogenous neuropeptides. We compared different extraction conditions for the recovery of neuropeptides and the formation of protein breakdown fragments from mouse hypothalami. Sonication and heating in water (70 degrees C for 20 min) followed by cold acid and centrifugation enabled the efficient extraction of many neuropeptides without the formation of protein degradation fragments seen with hot acid extractions. The hot water/cold acid extraction procedure resulted in the reproducible recovery of many hypothalamic peptides, including several novel peptides. 相似文献
996.
997.
Niu Baolin Lei Xiaohong Xu Qingling Ju Yi Xu Dongke Mao Liya Li Jing Zheng Yufan Sun Ning Zhang Xin Mao Yimin Li Xiaobo 《Cell biology and toxicology》2022,38(3):505-530
Cell Biology and Toxicology - Acetaminophen (APAP) overdose is a common cause of drug-induced liver injury (DILI). Ferroptosis has been recently implicated in APAP-induced liver injury (AILI).... 相似文献
998.
She Yang Gao Xiang Jing Xin Wang Jing Dong Yibei Cui Jinzi Xue Huidan Li Zhengke Zhu Derui 《Journal of applied phycology》2022,34(3):1281-1291
Journal of Applied Phycology - A new strain of Eustigmatophyceae, Vischeria sp. WL1, which accumulates oil droplets in the cells, was isolated from a large biological soil crust in the arid steppes... 相似文献
999.
Jiang Huihui Yang Xin Mi Miaomiao Wei Xiaonan Wu Hongyuan Xin Yu Jiao Liping Sun Shengjun Sun Chengming 《Molecular biology reports》2022,49(3):2097-2105
Molecular Biology Reports - PER2 gene methylation is closely related to the occurrence and progress of some cancers, but there is no method to quantitatively detect PER2 methylation in conventional... 相似文献
1000.
Su Jiaojiao Pang Wenjing Zhang Aisen Li Lei Yao Weiyan Dai Xin 《Molecular biology reports》2022,49(3):1711-1720
Molecular Biology Reports - New onset diabetes mellitus demonstrates a roughly correlation with pancreatic cancer (PaC), which is unique in PaC and was named as PaC-induced DM, but the inner... 相似文献