Abstract
One of the previously isolated genes from Arabidopsis thaliana, designated AtM532, encodes a protein homologous to yeast Rpf2, a pre-rRNA processing factor responsible for the processing of 27Spre-rRNA to 25SrRNA and 5.8SrRNA in ribosome biogenesis. AtM532 gene is highly expressed in meristems and nuclear/nucleolar localization of that product was confirmed by expressing the GFP::AtM532 fusion protein in onion epidermal cells. The AtM532 gene exists as a single copy in the genome and the homozygous for the T-DNA insertion causes embryonic lethal phenotype. Transgenic plants expressing anti-sense AtM532 that show reduced levels of AtM532 protein accumulation exhibited abnormal growth with high accumulation levels of 27SPre-rRNA. Moreover, interaction of AtM532 protein with a ribosome-associated protein was confirmed by the yeast two-hybrid method. These results suggest that AtM532 is a pre-rRNA processing factor.
