Human fatty aldehyde dehydrogenase gene (ALDH10): organization and tissue-dependent expression

Mutations in the fatty aldehyde dehydrogenase gene (ALDH10) are responsible for Sjögren-Larsson syndrome (De Laurenzi et al., 1996). In this study, the expression and the genomic organization of the ALDH10 gene are reported. The gene spans approximately 31 kb and consists of 10 exons and 9 introns. All exon-intron junction sequences match the classical GT/AG rule. Both S1 nuclease protection assay and primer extension study suggest that the transcription initiation site is located 195 nucleotides upstream from the ATG codon. No canonical TATA box can be found in the 5'-flanking sequence of the gene, but a CCAAT-like box was found 58 bp upstream of the putative transcription start site. Sequence analysis of the 5'-flanking region revealed numerous potential binding sites for transcription factors Sp1 and AP-2 and one putative HIP-1 binding site. Northern blot analysis of poly(A)+ RNA from various tissues revealed two mRNA species, with sizes around 4.0 and 2.0 kb, that are derived from the differential use of two polyadenylation sites. Although this gene is expressed in a variety of human tissues, the expression level of ALDH10 in the liver and skeletal muscle appears to be higher than that in other tissues examined.