VH1/BRL2 receptor-like kinase interacts with vascular-specific adaptor proteins VIT and VIK to influence leaf venation.
VH1/BRL2 is a receptor-like kinase of the BRI1 family with a role in vascular development. In developing Arabidopsis leaves it is expressed first in ground cells and then becomes restricted to provascular and procambial cells as venation forms. We isolated proteins interacting with the activated (phosphorylated) cytoplasmic domain of VH1/BRL2, and found that most belong to three processes: proteasome activity, vesicle traffic and intracellular signal transduction. Two adaptor proteins are included that we named VIT [VH1-interacting tetratricopeptide repeat (TPR)-containing protein] and VIK (VH1-interacting kinase), which are co-expressed in the same cells as VH1/BRL2 at two distinct time points in vein differentiation. Mutation of either adaptor or of VH1 results in vein pattern defects and in alterations in response to auxin and brassinosteroids. We propose that these two adaptors facilitate the diversification and amplification of a ligand signal perceived by VH1/BRL2 in multiple downstream pathways affecting venation.
Ceserani
Teresa
T
Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520-8104, USA.
Trofka
Anna
A
Gandotra
Neeru
N
Nelson
Timothy
T
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism; D020930:MAP Kinase Kinase Kinases / Q000235:genetics / Q000378:metabolism; D016254:Mutagenesis, Insertional; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics / Q000254:growth & development*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D014158:Transcription, Genetic
D048868:Adaptor Proteins, Signal Transducing; D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; D011494:Protein Kinases; C472132:VH1 protein, Arabidopsis; D020930:MAP Kinase Kinase Kinases