The COBRA family of putative GPI-anchored proteins in Arabidopsis. A new fellowship in expansion.
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.
Roudier
François
F
Department of Biology, New York University, New York, NY 10003, USA.
Schindelman
Gary
G
DeSalle
Rob
R
Benfey
Philip N
PN
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
D029681:Arabidopsis Proteins; C427475:COB protein, Arabidopsis; D017261:Glycosylphosphatidylinositols; D008562:Membrane Glycoproteins