Interactions of Oryza sativa OsCONTINUOUS VASCULAR RING-LIKE 1 (OsCOLE1) and OsCOLE1-INTERACTING PROTEIN reveal a novel intracellular auxin transport mechanism.
Little is known about the transport mechanism of intracellular auxin. Here, we report two vacuole-localized proteins, Oryza sativa OsCONTINUOUS VASCULAR RING-LIKE 1 (OsCOLE1) and OsCOLE1-INTERACTING PROTEIN (OsCLIP), that regulate intracellular auxin transport and homoeostasis. Overexpression of OsCOLE1 markedly increased the internode length and auxin content of the stem base, whereas these parameters were decreased in RNA interference (RNAi) plants. OsCOLE1 was localized on the tonoplast and preferentially expressed in mature tissues. We further identified its interacting protein OsCLIP, which was co-localized on the tonoplast. Protein-protein binding assays demonstrated that the N-terminus of OsCOLE1 directly interacted with OsCLIP in yeast cells and the rice protoplast. Furthermore, (3) H-indole-3-acetic acid ((3) H-IAA) transport assays revealed that OsCLIP transported IAA into yeast cells, which was promoted by OsCOLE1. The results indicate that OsCOLE1 affects rice development by regulating intracellular auxin transport through interaction with OsCLIP, which provides a new insight into the regulatory mechanism of intracellular transport of auxin and the roles of vacuoles in plant development.
Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Haidian District, Beijing, China.
Fei
F
Liu
Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Haidian District, Beijing, China.
Lan
L
Zhang
Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Haidian District, Beijing, China.
Yanzhong
Y
Luo
Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Haidian District, Beijing, China.
Miaoyun
M
Xu
Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Haidian District, Beijing, China.
Yunliu
Y
Fan
Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Haidian District, Beijing, China.
Lei
L
Wang
D001692:Biological Transport; D007210:Indoleacetic Acids / Q000378:metabolism*; D042541:Intracellular Space / Q000378:metabolism*; D009280:Naphthaleneacetic Acids / Q000378:metabolism; D012275:Oryza / Q000033:anatomy & histology / Q000378:metabolism*; D010641:Phenotype; D010940:Plant Proteins / Q000378:metabolism*; D018547:Plant Stems / Q000378:metabolism; D030821:Plants, Genetically Modified; D011485:Protein Binding; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013347:Subcellular Fractions / Q000378:metabolism; D014617:Vacuoles / Q000378:metabolism
D007210:Indoleacetic Acids; D009280:Naphthaleneacetic Acids; D010940:Plant Proteins; C034182:1-naphthaleneacetic acid
OsCOV-LIKE 1 (OsCOLE1); OsCOV-LIKE 1 (OsCOLE1)-INTERACTING PROTEIN (OsCLIP); auxin transport; rice (Oryza sativa); vacuole