A puromycin-sensitive aminopeptidase is essential for meiosis in Arabidopsis thaliana.
Plant Cell
; 16(11): 2895-909, 2004 Nov.
Article
en En
| MEDLINE
| ID: mdl-15522847
Puromycin-sensitive aminopeptidases (PSAs) participate in a variety of proteolytic events essential for cell growth and viability, and in fertility in a broad range of organisms. We have identified and characterized an Arabidopsis thaliana mutant (mpa1) from a pool of T-DNA tagged lines that lacks PSA activity. This line exhibits reduced fertility, producing shorter siliques (fruits) bearing a lower number of seeds compared with wild-type plants. Cytogenetic characterization of meiosis in the mutant line reveals that both male and female meiosis are defective. In mpa1, early prophase I appears normal, but after pachytene most of the homologous chromosomes are desynaptic, thus, by metaphase I a high level of univalence is observed subsequently leading to abnormal chromosome segregation. Wild-type plants treated with specific inhibitors of PSA show a very similar desynaptic phenotype to that of the mutant line. A fluorescent PSA-specific bioprobe, DAMPAQ-22, reveals that the protein is maximally expressed in wild-type meiocytes during prophase I and is absent in mpa1. Immunolocalization of meiotic proteins showed that the meiotic recombination pathway is disrupted in mpa1. Chromosome pairing and early recombination appears normal, but progression to later stages of recombination and complete synapsis of homologous chromosomes are blocked.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Arabidopsis
/
Proteínas de Arabidopsis
/
Aminopeptidasas
/
Meiosis
/
Mutación
Tipo de estudio:
Diagnostic_studies
Idioma:
En
Revista:
Plant Cell
Asunto de la revista:
BOTANICA
Año:
2004
Tipo del documento:
Article
País de afiliación:
Reino Unido
Pais de publicación:
Reino Unido