title: BAM receptors regulate stem cell specification and organ development through complex interactions with CLAVATA signaling.
abstract: The CLAVATA1 (CLV1) receptor kinase regulates stem cell specification at shoot and flower meristems of Arabidopsis. Most clv1 alleles are dominant negative, and clv1 null alleles are weak in phenotype, suggesting additional receptors functioning in parallel. We have identified two such parallel receptors, BAM1 and BAM2. We show that the weak nature of the phenotype of clv1 null alleles is dependent on BAM activity, with bam clv mutants exhibiting severe defects in stem cell specification. Furthermore, BAM activity in the meristem depends on CLV2, which is required in part for CLV1 function. In addition, clv1 mutants enhance many of the Bam(-) organ phenotypes, indicating that, contrary to current understanding, CLV1 function is not specific to the meristem. CLV3 encodes a small, secreted peptide that acts as the ligand for CLV1. Mutations in clv3 lead to increased stem cell accumulation. Surprisingly, bam1 and bam2 mutants suppress the phenotype of clv3 mutants. We speculate that in addition to redundant function in the meristem center, BAM1 and BAM2 act to sequester CLV3-like ligands in the meristem flanks.
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109-1048, USA.
authors.forename: Brody J
authors.initials: BJ
authors.lastname: Deyoung
authors.forename: Steven E
authors.initials: SE
authors.lastname: Clark
mesh_terms: D000483:Alleles; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D018519:Meristem / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D038081:Organogenesis; D010641:Phenotype; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*
chemical_list: C118167:AT2G27250 protein, Arabidopsis; D029681:Arabidopsis Proteins; C401621:CLV2 protein, Arabidopsis; D008565:Membrane Proteins; D020794:Receptor Protein-Tyrosine Kinases; C519658:BAM1 protein, Arabidopsis; C519659:BAM2 protein, Arabidopsis; C118166:CLV1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases
references.citation: Plant Cell. 2006 Jul;18(7):1667-80
references.pmid: 16751349
references.citation: Science. 2006 Aug 11;313(5788):845-8
references.pmid: 16902141
references.citation: Development. 1998 Oct;125(19):3843-51
references.pmid: 9729492
references.citation: Science. 2008 Jan 18;319(5861):294
references.pmid: 18202283
references.citation: Development. 1996 Jan;122(1):87-96
references.pmid: 8565856
references.citation: Science. 2000 Jul 28;289(5479):617-9
references.pmid: 10915624
references.citation: Plant Physiol. 2001 Jul;126(3):939-42
references.pmid: 11457943
references.citation: Plant Cell. 2003 May;15(5):1095-110
references.pmid: 12724536
references.citation: Trends Plant Sci. 2003 Aug;8(8):394-401
references.pmid: 12927973
references.citation: Proc Natl Acad Sci U S A. 1997 Sep 16;94(19):10467-72
references.pmid: 9294234
references.citation: Gene. 2004 Feb 18;327(1):37-49
references.pmid: 14960359
references.citation: Development. 2004 Nov;131(22):5649-57
references.pmid: 15509765
references.citation: Curr Biol. 2003 Feb 4;13(3):179-88
references.pmid: 12573213
references.citation: Curr Opin Genet Dev. 2003 Oct;13(5):551-7
references.pmid: 14550423
references.citation: Funct Plant Biol. 2006 Aug;33(8):723-730
references.pmid: 32689282
references.citation: Plant Cell. 1999 Oct;11(10):1925-34
references.pmid: 10521522
references.citation: Dev Biol. 2005 Sep 1;285(1):272-84
references.pmid: 16112663
references.citation: Plant Mol Biol. 2003 Feb;51(3):415-25
references.pmid: 12602871
references.citation: Plant Cell. 2005 Jan;17(1):61-76
references.pmid: 15598805
references.citation: J Cell Sci. 2003 May 1;116(Pt 9):1659-66
references.pmid: 12665547
references.citation: Cell. 1997 May 16;89(4):575-85
references.pmid: 9160749
references.citation: Science. 2006 Aug 11;313(5788):842-5
references.pmid: 16902140
references.citation: Plant Physiol. 2006 Feb;140(2):726-33
references.pmid: 16407446
references.citation: Cell. 1998 Dec 11;95(6):805-15
references.pmid: 9865698
references.citation: Plant J. 2006 Jan;45(1):1-16
references.pmid: 16367950
references.citation: Development. 2006 Dec;133(23):4691-8
references.pmid: 17079273
references.citation: Plant Cell. 2005 Mar;17(3):691-704
references.pmid: 15705957
references.citation: Plant Cell. 1999 Mar;11(3):393-406
references.pmid: 10072399
references.citation: Development. 2005 Mar;132(6):1235-45
references.pmid: 15716347
references.citation: Plant Cell. 1997 Jul;9(7):1067-1076
references.pmid: 12237376
references.citation: Development. 1993 Oct;119(2):397-418
references.pmid: 8287795
references.citation: Development. 2003 Jul;130(14):3163-73
references.pmid: 12783788
references.citation: Plant Cell. 2005 Sep;17(9):2542-53
references.pmid: 16055633
references.citation: Cell. 2000 Mar 17;100(6):635-44
references.pmid: 10761929
references.citation: Development. 2000 Apr;127(8):1661-70
references.pmid: 10725242
references.citation: Plant Cell. 2003 May;15(5):1198-211
references.pmid: 12724544
references.citation: Plant Mol Biol. 2001 Jul;46(5):505-13
references.pmid: 11516143