CELL DIVISION CONTROL PROTEIN48(CDC48)is essential for membrane fusion,protein degradation,and other cellular processes.Here,we revealed the crucial role of CDC48B in regulating periclinal cell division in roots by an...CELL DIVISION CONTROL PROTEIN48(CDC48)is essential for membrane fusion,protein degradation,and other cellular processes.Here,we revealed the crucial role of CDC48B in regulating periclinal cell division in roots by analyzing the recessive gen1 mutant.We identified the GEN1 gene through map-based cloning and verified that GEN1 encodes CDC48B.gen1 showed severely inhibited root growth,increased periclinal cell division in the endodermis,defective middle cortex(MC)formation,and altered ground tissue patterning in roots.Consistent with these phenotypes,CYCLIND 6;1(CYCD6;1),a periclinal cell division marker,was upregulated in gen1 compared to Col-0.The ratio of SHR_(pro):SHR-GFP fluorescence in pre-dividing nuclei versus the adjacent stele decreased by 33%in gen1,indicating that the trafficking of SHORT-ROOT(SHR)decreased in gen1 when endodermal cells started to divide.These findings suggest that the loss of function of CDC48B inhibits the intercellular trafficking of SHR from the stele to the endodermis,thereby decreasing SHR accumulation in the endodermis.These findings shed light on the crucial role of CDC48B in regulating periclinal cell division in roots.展开更多
In plants,thousands of nucleus-encoded proteins translated in the cytosol are sorted to chloroplasts and mitochondria by binding to specific receptors of the TOC(translocon on the outer chloroplast membrane)and the TO...In plants,thousands of nucleus-encoded proteins translated in the cytosol are sorted to chloroplasts and mitochondria by binding to specific receptors of the TOC(translocon on the outer chloroplast membrane)and the TOM(translocon on the outer mitochondrial membrane)complexes for import into those organelles.The degradation pathways for these receptors are unclear.Here,we discovered a converged ubiquitin-proteasome pathway for the degradation of Arabidopsis thaliana TOC and TOM tail-anchored receptors.The receptors are ubiquitinated by E3 ligase(s)and pulled from the outer membranes by the AAA+adenosine triphosphatase CDC48,after which a previously uncharacterized cytosolic protein,transmembrane domain(TMD)-binding protein for tail-anchored outer membrane proteins(TTOP),binds to the exposed TMDs at the C termini of the receptors and CDC48,and delivers these complexes to the 26S proteasome.展开更多
基金The Program of Tianjin Municipal Science&Technology Project(11ZCZDSY08100)The Program of“One Hundred Talented People”of the Chinese Academy of Sciences(KSCW2-YW-BR-4)National Natural Science Foundation of China(81273275)~~
基金supported by the National Natural Science Foundation of China (31570291, 31570246)Funds of Shandong “Double Tops” Program (YL2017YSTD03)+3 种基金Shandong “Foreign Experts Double Hundred” Program (WST2017008)Shandong Key Basic Research (ZR2018ZC08N1)Natural Science Foundation of Heilongjiang Province (C2016002)the Fundamental Research Funds for the Central Universities (2572019CT03).
文摘CELL DIVISION CONTROL PROTEIN48(CDC48)is essential for membrane fusion,protein degradation,and other cellular processes.Here,we revealed the crucial role of CDC48B in regulating periclinal cell division in roots by analyzing the recessive gen1 mutant.We identified the GEN1 gene through map-based cloning and verified that GEN1 encodes CDC48B.gen1 showed severely inhibited root growth,increased periclinal cell division in the endodermis,defective middle cortex(MC)formation,and altered ground tissue patterning in roots.Consistent with these phenotypes,CYCLIND 6;1(CYCD6;1),a periclinal cell division marker,was upregulated in gen1 compared to Col-0.The ratio of SHR_(pro):SHR-GFP fluorescence in pre-dividing nuclei versus the adjacent stele decreased by 33%in gen1,indicating that the trafficking of SHORT-ROOT(SHR)decreased in gen1 when endodermal cells started to divide.These findings suggest that the loss of function of CDC48B inhibits the intercellular trafficking of SHR from the stele to the endodermis,thereby decreasing SHR accumulation in the endodermis.These findings shed light on the crucial role of CDC48B in regulating periclinal cell division in roots.
基金supported by the Science,Technology and Innovation Commission of Shenzhen Municipality(Basic Research Program 201708183000803)the Hong Kong Research Grants Council Area of Excellence Scheme(AoE/M-403/16)the Innovation and Technology Fund(Funding Support to State Key Laboratory of Agrobiotechnology)of the Hong Kong Special Administrative Region,China.
文摘In plants,thousands of nucleus-encoded proteins translated in the cytosol are sorted to chloroplasts and mitochondria by binding to specific receptors of the TOC(translocon on the outer chloroplast membrane)and the TOM(translocon on the outer mitochondrial membrane)complexes for import into those organelles.The degradation pathways for these receptors are unclear.Here,we discovered a converged ubiquitin-proteasome pathway for the degradation of Arabidopsis thaliana TOC and TOM tail-anchored receptors.The receptors are ubiquitinated by E3 ligase(s)and pulled from the outer membranes by the AAA+adenosine triphosphatase CDC48,after which a previously uncharacterized cytosolic protein,transmembrane domain(TMD)-binding protein for tail-anchored outer membrane proteins(TTOP),binds to the exposed TMDs at the C termini of the receptors and CDC48,and delivers these complexes to the 26S proteasome.
