CONSERVATION OF THE HUMAN BREAST BASIC CONSERVED 1-GENE IN THE PLANT KINGDOM - CHARACTERIZATION OF A CDNA CLONE FROM ARABIDOPSIS-THALIANA

Based on low-stringency genomic Southern analysis, the recently descri bed human breast basic conserved 1 (BBC1) gene has been proposed to be conserved throughout Eukaryota [Adams et al., Hum. Mel. Genet. 1 (199 2) 91-96]. We have isolated and characterized a cDNA clone (AtBBC1) wh ich corresponds to a BBC1 homologue from the model plant species, Arab idopsis thalinana. Furthermore, upon Northern analysis, the AtBBC1 pro be detects related transcripts in various dicotyledenous and monocotyl edonous plant species, indicating that actively transcribed BBC1-relat ed genes are widespread in the plant kingdom. BBC1 has been shown to b e expressed in all mammalian tissues examined [Adams et al., Hum. Mel. Genet. 1 (1992) 91-96]; similarly, here the AtBBC1 transcript has bee n detected in a variety of A. thaliana organs. In addition, the abunda nce of the AtBBC1 mRNA is developmentally regulated during the course of fruit maturation, and is positively correlated with active cell div ision.