Control of endoreduplication of trichome by RPT2a, a subunit of the 19S proteasome in Arabidopsis.
J Plant Res
; 123(5): 701-6, 2010 Sep.
Article
em En
| MEDLINE
| ID: mdl-20195883
ABSTRACT
The ubiquitin/26S proteasome pathway plays a central role in the degradation of short-lived regulatory proteins to control many cellular events. The Arabidopsis knockout mutant rpt2a, which contains a defect in the AtRPT2a subunit of the 26S proteasome regulatory particle, showed enlarged leaves caused by increased cell size that correlated with increased ploidy caused by extended endoreduplication. To clarify the role of RPT2a in endoreduplication control, trichome development was genetically examined in further detail. RHL1 and GL3 encode proteins that have a role in the positive regulation of endocycle progression in trichomes. The rhl1 mutants are stalled at 8C and have trichomes with only a single branch. The rpt2a mutation did not alter the rhl1 mutant phenotype, and trichomes of double rpt2a rhl1 mutants resembled that of single rhl1 mutants. On the other hand, the rpt2a mutation suppressed the gl3 phenotype (stalled at 16C, two trichome branches), and trichomes of the double rpt2a gl3 mutant resembled those of the wild type (WT) plants. Together, these data suggest that RPT2a functions to negatively regulate endocycle progression following completion of the third endoreduplication step mediated by RHL1 (8C-16C).
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Base de dados:
MEDLINE
Assunto principal:
Arabidopsis
/
Proteínas de Arabidopsis
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Complexo de Endopeptidases do Proteassoma
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article