title: The COBRA family of putative GPI-anchored proteins in Arabidopsis. A new fellowship in expansion.
abstract: Identification of regulatory molecules that determine the extent and direction of expansion is necessary to understand how cell morphogenesis is controlled in plants. We recently identified COB (COBRA) as a key regulator of the orientation of cell expansion in the root. Analysis of the Arabidopsis genome sequence indicated that COB belongs to a multigene family consisting of 12 members, all predicted to encode glycosylphosphatidylinositol-anchored proteins. All but two of the COBL (COB-like) genes are expressed in most organs examined, suggesting possible redundancy. Sequence comparisons, phylogenetic analyses, and exon-intron positions revealed that the COB family is composed of two main subgroups sharing a common architecture, one subgroup being characterized by an additional N-terminal domain. Identification of expressed sequence tags corresponding to potential orthologs in other plant species suggested that COB-related functions are required in all vascular plants. Together, these results indicate that COB family members are likely to be important new players at the plasma membrane-cell wall interface.
authors.affiliation: Department of Biology, New York University, New York, NY 10003, USA.
authors.forename: François
authors.initials: F
authors.lastname: Roudier
authors.forename: Gary
authors.initials: G
authors.lastname: Schindelman
authors.forename: Rob
authors.initials: R
authors.lastname: DeSalle
authors.forename: Philip N
authors.initials: PN
authors.lastname: Benfey
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins; D002455:Cell Division / Q000235:genetics / Q000502:physiology; D002462:Cell Membrane / Q000378:metabolism; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D018506:Gene Expression Regulation, Plant; D017261:Glycosylphosphatidylinositols / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; C427475:COB protein, Arabidopsis; D017261:Glycosylphosphatidylinositols; D008562:Membrane Glycoproteins