Cloning and Expression of a cDNA Encoding a Constitutively Expressed Rat Liver Cytosolic Aldehyde Dehydrogenase

Abstract

Aldehydedehydrogenase (ALDH) is a ubiquitous enzyme expressed in nearly all mammalian tissues and subcellular organelles. Rat liver contains multiple isoforms of ALDH, including the following for which cDNAs have been cloned: phenobarbital (PB)inducible cytosolic ALDHI (Dunn et al., 1989), mitochondrial ALDH2 (Farres et al., 1989), microsomal ALDH3 (Miyauchi et al., 1991), and tumor-associated cytosolic ALDH3 (Jones et al., 1988). However, a constitutively expressed rat liver cytosolic ALDHI has been difficult to characterize based on confusion in the literature as to whether or not this ALDH isoform even exists (Tottmar, et al., 1973; Lindahl and Evces, 1984; Berger and Weiner, 1977; Tank et al., 1981; Truesdale-Mahoney et al., 1981; Cao et al., 1989). In order to study and characterize this ALDHI isoform, we have cloned and expressed a cDNA encoding a rat liver constitutively expressed cytosolic ALDHI.