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991.
Phosphorylation of Pkp1 by RIPK4 regulates epidermal differentiation and skin tumorigenesis 下载免费PDF全文
Philbert Lee Shangwen Jiang Yuanyuan Li Jiping Yue Xuewen Gou Shao‐Yu Chen Yingming Zhao Markus Schober Minjia Tan Xiaoyang Wu 《The EMBO journal》2017,36(13):1963-1980
Tissue homeostasis of skin is sustained by epidermal progenitor cells localized within the basal layer of the skin epithelium. Post‐translational modification of the proteome, such as protein phosphorylation, plays a fundamental role in the regulation of stemness and differentiation of somatic stem cells. However, it remains unclear how phosphoproteomic changes occur and contribute to epidermal differentiation. In this study, we survey the epidermal cell differentiation in a systematic manner by combining quantitative phosphoproteomics with mammalian kinome cDNA library screen. This approach identified a key signaling event, phosphorylation of a desmosome component, PKP1 (plakophilin‐1) by RIPK4 (receptor‐interacting serine–threonine kinase 4) during epidermal differentiation. With genome‐editing and mouse genetics approach, we show that loss of function of either Pkp1 or Ripk4 impairs skin differentiation and enhances epidermal carcinogenesis in vivo. Phosphorylation of PKP1's N‐terminal domain by RIPK4 is essential for their role in epidermal differentiation. Taken together, our study presents a global view of phosphoproteomic changes that occur during epidermal differentiation, and identifies RIPK‐PKP1 signaling as novel axis involved in skin stratification and tumorigenesis. 相似文献
992.
993.
M. Sang X. -C. Qin W. -D. Wang J. Xie X. -B. Chen K. B. Wang J. -P. Zhang L. -B. Li T. Y. Kuang 《Photosynthetica》2011,49(1):48-54
The generation of superoxide anion radical (O2
·−) in the cytochrome b
6
f complex (Cyt b
6
f) of spinach under high-light illumination was studied using electron paramagnetic resonance spectroscopy. The generation
of O2
·− was lost in the absence of molecular oxygen. It was also suppressed in the presence of NaN3 and could be scavenged by extraneous antioxidants such as ascorbate, β-carotene, and glutathione. The results also indicate that O2
·−, which is produced under high-light illumination of the Cyt b
6
f from spinach, might be generated from a reaction involing 1O2, and the Rieske Fe-S protein could serve as the electron donor in the O2
·− production. The mechanism of photoprotection of the Cyt b
6
f complex by antioxidants is discussed. 相似文献
994.
Chia-Hsuan Chen Hsiu-Lin Huang Mu-Tzu Chang Li-Chia Chiang Shih-Lin Cheng Bing-Tsan Liu Chih-Hua Wang Ming-Che Wu Mu-Chiou Huang 《Biologia》2011,66(6):1196-1201
The complete mitochondrial genome sequence of the Formosan sambar (Rusa unicolor swinhoei) was obtained by DNA sequencing based on PCR fragments amplified by 26 primer pairs designed by ourselves. The results indicated
that the mtDNA is 16,505 bp in size. This is the first report on mitochondrial DNA (mtDNA) sequence analysis of the Formosan
sambar and the sequence was deposited in the GenBank database under the accession number DQ989636. The complete mitochondrial
sequence included the following gene sequences: 12S and 16S rRNAs, 22 tRNAs and 13 protein-coding genes. The base composition
of the sequence was as follows: A, 33.51%; T, 28.97%; C, 24.07%; and G, 13.46%. The mitochondrial D-loop region was also analyzed
for comparative purposes in the Formosan sambar and 13 other species within the Cervidae family using neighbour-joining method.
The phylogenetic tree demonstrated that there are two separate groups, a European type and an Asian type, within the Cervidae
family. The D-loop sequences of mtDNA of 24 Formosan sambar animals were compared, and the results showed that the Formosan
sambar can be divided into two clades. 相似文献
995.
An acidic microenvironment induces disruption of adherens junctions (AJs) of hepatoma cells. This study investigated the impact of an acidic extracellular pH (pHe) on p120-catenin (p120-ctn) serine phosphorylation. pH 6.6 treatment increased intracellular calcium levels, activated protein kinase C (PKC)α and PKCδ, and decreased serine phosphorylation of p120-ctn. Further knockdown of PKCα and δ by small interference RNA (siRNA) prevented the pH 6.6-induced downregulation of p120-ctn at AJ and the serine dephosphorylation of p120-ctn. Moreover, PP2 pretreatment and siRNA of c-Src abrogated the pH 6.6-induced PKCδ activation. Together, the c-Src-PKCδ cascade and PKCα regulate the acidic pHe-induced AJ disruption. 相似文献
996.
997.
While sulfur dioxide (SO2) has been previously known for its toxicological effects, it is now known to be produced endogenously in mammals from sulfur-containing amino acid l-cysteine. l-cysteine is catalyzed by cysteine dioxygenase (CDO) to l-cysteinesulfinate, which converts to β-sulfinylpyruvate through transamination by aspartate aminotransferase (AAT), and finally spontaneously decomposes to pyruvate and SO2. The present study explored endogenous SO2 production, and AAT and CDO distribution in different rat tissue. SO2 content was highest in stomach, followed by tissues in the right ventricle, left ventricle, cerebral gray matter, pancreas, lung, cerebral white matter, renal medulla, spleen, renal cortex and liver. AAT activity and AAT1 mRNA expression were highest in the left ventricle, while AAT1 protein expression was highest in the right ventricle. AAT2 and CDO mRNA expressions were both highest in liver tissue. AAT2 protein expression was highest in the renal medulla, but CDO protein expression was highest in liver tissue. In all tissues, AAT1 and AAT2 were mainly distributed in the cytoplasm rather than the nucleus. These observed differences among tissues endogenously generating SO2 and associated enzymes are important in implicating the discovery of SO2 as a novel endogenous signaling molecule. 相似文献
998.
目的研究大鼠局灶性脑缺血再灌注损伤后神经元和星形胶质细胞表达量的动态演变及各自cyclin D1的表达差异。方法建立大鼠大脑中动脉阻塞(MCAO)再灌注模型,随机分为再灌注后1d组,3d组,7d组,14d组和假手术组,应用流式细胞术检测各组再灌注后不同时间点神经元和星形胶质细胞数量变化及各自cyclin D1的表达。结果缺血侧梗死边缘区皮质星形胶质细胞的表达增加,而神经元的表达下降,与假手术组比较有明显差异(P〈0.05);神经元和星形胶质细胞中各自cyclin D1的表达在再灌注7d、14d后表达上调,且星形胶质细胞中的cyclinD1增加更明显,与假手术组比较有统计学差异(P〈0.05)。结论大鼠脑缺血再灌注后,缺血侧梗死边缘区皮质星形胶质细胞和神经元的cyclinD1表达均有不同程度的上调,星形胶质细胞的cyclin D1表达上调比神经元的更为显著。 相似文献
999.
1000.