The glycerophosphoryl diester phosphodiesterase-like proteins SHV3 and its homologs play important roles in cell wall organization.
Despite the importance of extracellular events in cell wall organization and biogenesis, the mechanisms and related factors are largely unknown. We isolated an allele of the shaven3 (shv3) mutant of Arabidopsis thaliana, which exhibits ruptured root hair cells during tip growth. SHV3 encodes a novel protein with two tandemly repeated glycerophosphoryl diester phosphodiesterase-like domains and a glycosylphosphatidylinositol anchor, and several of its paralogs are found in Arabidopsis. Here, we report the detailed characterization of mutants of SHV3 and one of its paralogs, SVL1. The shv3 and svl1 double mutant exhibited additional defects, including swollen guard cells, aberrant expansion of the hypocotyl epidermis and ectopic lignin deposits, suggesting decreased rigidity of the cell wall. Fourier-transform infrared spectroscopy and measurement of the cell wall components indicated an altered cellulose content and pectin modification with cross-linking in the double mutant. Furthermore, we found that the ruptured root hair phenotype of shv3 was suppressed by increasing the amount of borate, which is supposed to be involved in pectic polysaccharide cross-linking, in the medium. These findings indicate that SHV3 and its paralogs are novel important factors involved in primary cell wall organization.
Hayashi
Shimpei
S
International Graduate School of Arts and Sciences, Yokohama City University, 1-7-29 Suehiro, Tsurumi, Yokohama, 230-0045 Japan.
Ishii
Tadashi
T
Matsunaga
Toshiro
T
Tominaga
Rumi
R
Kuromori
Takashi
T
Wada
Takuji
T
Shinozaki
Kazuo
K
Hirayama
Takashi
T
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000166:cytology / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002473:Cell Wall / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D002482:Cellulose / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D017343:Genes, Plant; D018546:Hypocotyl / Q000166:cytology / Q000201:enzymology / Q000235:genetics; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D010368:Pectins / Q000378:metabolism; D010641:Phenotype; D010727:Phosphoric Diester Hydrolases / Q000235:genetics / Q000378:metabolism*; D019441:Plant Epidermis / Q000648:ultrastructure; D018517:Plant Roots / Q000166:cytology / Q000201:enzymology / Q000235:genetics; D030821:Plants, Genetically Modified / Q000166:cytology / Q000201:enzymology / Q000235:genetics; D017354:Point Mutation; D018749:RNA, Plant / Q000235:genetics; D017550:Spectroscopy, Fourier Transform Infrared
D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D018749:RNA, Plant; C036483:T-DNA; D010368:Pectins; D002482:Cellulose; D010727:Phosphoric Diester Hydrolases; C038133:glycerophosphodiester phosphodiesterase