Apum23_col3

ABSTRACT: Gene expression analyses of three-week old soil grown wild-type (Col-3) and apum23-1 mutant. Expression profiling was conducted as an attempt to identify the genes differentially regulated in apum23-1 mutant This study was under taken to characterize a member of pumilio family, APUM23 in Arabidopsis. Pumilio, an RNA-binding protein (RBP) containing tandem repeat PUF domains, has been known to repress translational activity in early embryogenesis and polarized cells of non-plant species. Although Pumilio proteins have been characterized in many eukaryotes, their roles in plants are unknown. We detail the characterization of an Arabidopsis Pumilio gene, APUM23. APUM23 is constitutively expressed with higher level in metabolically active tissues, and upregulated in the presence of either glucose or sucrose. The T-DNA insertion mutants apum23-1 and apum23-2 showed slow growth with serrated and scrunched leaves, abnormal venation pattern, and distorted organization of the palisade parenchyma cells, a phenotype reminiscent of nucleolin and ribosomal protein gene mutants. Intracellular localization studies indicate that APUM23 predominantly localizes to the nucleolus. Based on the localization, rRNA processing was examined in apum23 mutant. In apum23, 35S pre-rRNA and unprocessed 18S and 5.8S poly(A) rRNAs were accumulated without affecting steady-state levels of mature rRNAs, indicating that APUM23 participates in the degradation of rRNA by-products. The apum23 mutant showed increased levels of 18S rRNA biogenesis-related U3 and U14 snoRNAs, and accumulated RNAs within nucleolus. Our results suggest that APUM23 plays an important role in plant development via rRNA processing and ribosome biogenesis. To identify the genes affected in apum23-1 as compared to wild-type (Col-3) under normal growth conditions using Arabidopsis ATH1 Genome arrays (Affymetrix). RNA samples from these plants were used to generate biotin labelled (cDNA) probes, which were then hybridized to the microarray. For data set generation, three independent samples were used, three from Col-3 and three from apum23-1 plants grown on soil for 21 days.

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Yeon-Ki Kim 

PROVIDER: E-GEOD-23940 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress