Molecular cloning of a homologue of dad-1 gene in citrus: distinctive expression during fruit development

A cDNA homologue to the human defender against apoptotic death gene (dad-1) , which is involved in programmed cell death, was isolated from satsuma man darin (Citrus unshiu Marc.) fruit. It (Citdad-1-1) was 345 bp long, with a deduced protein sequence of 115 amino acids. Southern hybridization suggest s that dad-1-related sequences are present as a small gene family in the ci trus genome. Expression of Citdad-1-1 was progressively down-regulated in l eaves as they matured, but not in juice sac/segment epidermis (edible part) towards fruit ripening. The role of dad-1 during citrus development is als o discussed. (C) 2000 Elsevier Science B.V. All rights reserved.