title: OsMLO12, encoding seven transmembrane proteins, is involved with pollen hydration in rice.
abstract: Hydration is the first step in pollen germination. However, the process is not well understood. OsMLO12 is highly expressed in mature pollen grains; plants containing alleles caused by transfer DNA insertions do not produce homozygous progeny. Reciprocal crosses between wild-type and OsMLO12/osmlo12 plants showed that the mutant alleles were not transmitted through the male gametophyte. Microscopic observations revealed that, although mutant grains became mature pollen with three nuclei, they did not germinate in vitro or in vivo due to a failure in hydration. The OsMLO12 protein has seven transmembrane motifs, with an N-terminal extracellular region and a C-terminal cytosolic region. We demonstrated that the C-terminal region mediates a calcium-dependent interaction with calmodulin. Our findings suggest that pollen hydration is regulated by MLO12, possibly through an interaction with calmodulin in the cytosol.
authors.affiliation: Department of Plant Molecular Systems Biotechnology, Crop Biotech Institute, Kyung Hee University, 1732 Deogyeong-daero, Giheung, Yongin, Gyeonggi, Korea.
authors.forename: Jakyung
authors.initials: J
authors.lastname: Yi
authors.forename: Suyoung
authors.initials: S
authors.lastname: An
authors.forename: Gynheung
authors.initials: G
authors.lastname: An
mesh_terms: D020816:Amino Acid Motifs; D002147:Calmodulin / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D005838:Genotype; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D016254:Mutagenesis, Insertional; D009928:Organ Specificity; D012275:Oryza / Q000166:cytology / Q000235:genetics / Q000502:physiology*; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D011058:Pollen / Q000166:cytology / Q000235:genetics / Q000502:physiology*; D054817:Pollination; D011993:Recombinant Fusion Proteins
chemical_list: D002147:Calmodulin; D008565:Membrane Proteins; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins