title: Differential Function of Arabidopsis SERK Family Receptor-like Kinases in Stomatal Patterning.
abstract: Plants use cell-surface-resident receptor-like kinases (RLKs) to sense diverse extrinsic and intrinsic cues and elicit distinct biological responses. In Arabidopsis, ERECTA family RLKs recognize EPIDERMAL PATTERNING FACTORS (EPFs) to specify stomatal patterning. However, little is known about the molecular link between ERECTA activation and intracellular signaling. We report here that the SOMATIC EMBRYOGENESIS RECEPTOR KINASE (SERK) family RLKs regulate stomatal patterning downstream of EPF ligands and upstream of a MAP kinase cascade. EPF ligands induce the heteromerization of ERECTA and SERK family RLKs. SERK and ERECTA family RLKs transphosphorylate each other. In addition, SERKs associate with the receptor-like protein (RLP) TMM, a signal modulator of stomata development, in a ligand-independent manner, suggesting that ERECTA, SERKs, and TMM form a multiprotein receptorsome consisting of different RLKs and RLP perceiving peptide ligands to regulate stomatal patterning. In contrast to the differential requirement of individual SERK members in plant immunity, cell-death control, and brassinosteroid (BR) signaling, all four functional SERKs are essential but have unequal genetic contributions to stomatal patterning, with descending order of importance from SERK3/BAK1 to SERK2 to SERK1 to SERK4. Although BR signaling connects stomatal development via multiple components, the function of SERKs in stomatal patterning is uncoupled from their involvement in BR signaling. Our results reveal that the SERK family is a shared key module in diverse Arabidopsis signaling receptorsomes and that different combinatorial codes of individual SERK members regulate distinct functions.
authors: Department of Biochemistry and Biophysics and Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843, USA.
authors: Xiangzong
authors: X
authors: Meng
authors: Department of Plant Pathology and Microbiology and Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843, USA.
authors: Xin
authors: X
authors: Chen
authors: Department of Biochemistry and Biophysics and Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843, USA.
authors: Hyunggon
authors: H
authors: Mang
authors: Department of Plant Pathology and Microbiology and Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843, USA.
authors: Chenglong
authors: C
authors: Liu
authors: Department of Plant Pathology and Microbiology and Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843, USA.
authors: Xiao
authors: X
authors: Yu
authors: Department of Plant Pathology and Microbiology and Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843, USA.
authors: Xiquan
authors: X
authors: Gao
authors: Howard Hughes Medical Institute and Department of Biology, University of Washington, Seattle, WA 98195, USA.
authors: Keiko U
authors: KU
authors: Torii
authors: Department of Biochemistry and Biophysics and Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843, USA. Electronic address: pinghe@tamu.edu.
authors: Ping
authors: P
authors: He
authors: Department of Plant Pathology and Microbiology and Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843, USA. Electronic address: lshan@tamu.edu.
authors: Libo
authors: L
authors: Shan
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D008024:Ligands; D054046:Plant Stomata / Q000254:growth & development / Q000378:metabolism; D011494:Protein Kinases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; D008024:Ligands; D011494:Protein Kinases