title: Arabidopsis COG Complex Subunits COG3 and COG8 Modulate Golgi Morphology, Vesicle Trafficking Homeostasis and Are Essential for Pollen Tube Growth.
abstract: Spatially and temporally regulated membrane trafficking events incorporate membrane and cell wall materials into the pollen tube apex and are believed to underlie the rapid pollen tube growth. In plants, the molecular mechanisms and physiological functions of intra-Golgi transport and Golgi integrity maintenance remain largely unclear. The conserved oligomeric Golgi (COG) complex has been implicated in tethering of retrograde intra-Golgi vesicles in yeast and mammalian cells. Using genetic and cytologic approaches, we demonstrate that T-DNA insertions in Arabidopsis COG complex subunits, COG3 and COG8, cause an absolute, male-specific transmission defect that can be complemented by expression of COG3 and COG8 from the LAT52 pollen promoter, respectively. No obvious abnormalities in the microgametogenesis of the two mutants are observed, but in vitro and in vivo pollen tube growth are defective. COG3 or COG8 proteins fused to green fluorescent protein (GFP) label the Golgi apparatus. In pollen of both mutants, Golgi bodies exhibit altered morphology. Moreover, γ-COP and EMP12 proteins lose their tight association with the Golgi. These defects lead to the incorrect deposition of cell wall components and proteins during pollen tube growth. COG3 and COG8 interact directly with each other, and a structural model of the Arabidopsis COG complex is proposed. We believe that the COG complex helps to modulate Golgi morphology and vesicle trafficking homeostasis during pollen tube tip growth.
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Tan
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Kun
authors.initials: K
authors.lastname: Cao
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Feng
authors.identifier: 0000-0003-1138-9472
authors.initials: F
authors.lastname: Liu
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Yingxin
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Pengxiang
authors.initials: P
authors.lastname: Li
authors.affiliation: School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
authors.forename: Caiji
authors.initials: C
authors.lastname: Gao
authors.affiliation: School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Ding
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Zhiyi
authors.initials: Z
authors.lastname: Lan
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Zhixuan
authors.initials: Z
authors.lastname: Shi
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Qingchen
authors.initials: Q
authors.lastname: Rui
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Yihong
authors.initials: Y
authors.lastname: Feng
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Yulong
authors.initials: Y
authors.lastname: Liu
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Yanxue
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Chengyun
authors.initials: C
authors.lastname: Wu
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
authors.forename: Liwen
authors.initials: L
authors.lastname: Jiang
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors.forename: Yiqun
authors.identifier: 0000-0003-0066-0239
authors.initials: Y
authors.lastname: Bao
mesh_terms: D033942:Adaptor Proteins, Vesicular Transport / Q000235:genetics*; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics*; D002462:Cell Membrane / Q000235:genetics* / Q000378:metabolism; D002473:Cell Wall / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D006031:Glycosylation; D006056:Golgi Apparatus / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D050505:Mutant Proteins / Q000235:genetics; D011058:Pollen / Q000235:genetics / Q000254:growth & development; D053205:Pollen Tube / Q000235:genetics* / Q000254:growth & development; D021122:Protein Subunits / Q000235:genetics*; D021381:Protein Transport / Q000235:genetics
chemical_list: D033942:Adaptor Proteins, Vesicular Transport; D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D008565:Membrane Proteins; D050505:Mutant Proteins; D021122:Protein Subunits; C036483:T-DNA