The FRIABLE1 gene product affects cell adhesion in Arabidopsis.
Cell adhesion in plants is mediated predominantly by pectins, a group of complex cell wall associated polysaccharides. An Arabidopsis mutant, friable1 (frb1), was identified through a screen of T-DNA insertion lines that exhibited defective cell adhesion. Interestingly, the frb1 plants displayed both cell and organ dissociations and also ectopic defects in organ separation. The FRB1 gene encodes a Golgi-localized, plant specific protein with only weak sequence similarities to known proteins (DUF246). Unlike other cell adhesion deficient mutants, frb1 mutants do not have reduced levels of adhesion related cell wall polymers, such as pectins. Instead, FRB1 affects the abundance of galactose- and arabinose-containing oligosaccharides in the Golgi. Furthermore, frb1 mutants displayed alteration in pectin methylesterification, cell wall associated extensins and xyloglucan microstructure. We propose that abnormal FRB1 action has pleiotropic consequences on wall architecture, affecting both the extensin and pectin matrices, with consequent changes to the biomechanical properties of the wall and middle lamella, thereby influencing cell-cell adhesion.
Max Planck Institute of Molecular Plant Physiology, Golm/Potsdam, Germany.
Lutz
L
Neumetzler
Tania
T
Humphrey
Shelley
S
Lumba
Stephen
S
Snyder
Trevor H
TH
Yeats
Björn
B
Usadel
Aleksandar
A
Vasilevski
Jignasha
J
Patel
Jocelyn K C
JK
Rose
Staffan
S
Persson
Dario
D
Bonetta
D017360:Arabidopsis / Q000166:cytology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D001089:Arabinose / Q000378:metabolism; D002448:Cell Adhesion / Q000235:genetics / Q000502:physiology*; D003001:Cloning, Molecular; D005690:Galactose / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D010368:Pectins / Q000378:metabolism
D029681:Arabidopsis Proteins; D010368:Pectins; D001089:Arabinose; C003181:polygalacturonic acid; D005690:Galactose