title: GNOM-LIKE 2, encoding an adenosine diphosphate-ribosylation factor-guanine nucleotide exchange factor protein homologous to GNOM and GNL1, is essential for pollen germination in Arabidopsis.
abstract: In flowering plants, male gametes are delivered to female gametophytes by pollen tubes. Although it is important for sexual plant reproduction, little is known about the genetic mechanism that controls pollen germination and pollen tube growth. Here we report the identification and characterization of two novel mutants, gnom-like 2-1 (gnl2-1) and gnl2-2 in Arabidopsis thaliana, in which the pollen grains failed to germinate in vitro and in vivo. GNL2 encodes a protein homologous to the adenosine diphosphate-ribosylation factor-guanine nucleotide exchange factors, GNOM and GNL1 that are involved in endosomal recycling and endoplasmic reticulum-Golgi vesicular trafficking. It was prolifically expressed in pollen grains and pollen tubes. The results of the present study suggest that GNL2 plays an important role in pollen germination.
authors.affiliation: State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, China.
authors.forename: Dong-Jie
authors.initials: DJ
authors.lastname: Jia
authors.forename: Xi
authors.initials: X
authors.lastname: Cao
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Xiao-Yun
authors.initials: XY
authors.lastname: Tan
authors.forename: Xue-Qin
authors.initials: XQ
authors.lastname: Zhang
authors.forename: Li-Qun
authors.initials: LQ
authors.lastname: Chen
authors.forename: De
authors.initials: D
authors.lastname: Ye
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000502:physiology*; D015139:Blotting, Southern; D005816:Genetic Complementation Test; D020662:Guanine Nucleotide Exchange Factors / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D030821:Plants, Genetically Modified / Q000235:genetics / Q000502:physiology; D011058:Pollen / Q000235:genetics / Q000502:physiology*; D053205:Pollen Tube / Q000235:genetics / Q000502:physiology; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; C522273:GNL1 protein, Arabidopsis; C088087:GNOM protein, Arabidopsis; D020662:Guanine Nucleotide Exchange Factors