Comparison of the chromosomal localization of murine and human glucocerebrosidase genes and of the deduced amino acid sequences

Abstract

To study structure-function relationships and molecular evolution, we determined the nucleotide sequence and chromosomal location of the gene encoding murine glucocerebrosidase (glucosylceramidase; D-glucosyl-N-acylsphingosine glucohydrolase, EC 3.2.1.45). In the protein coding region of the murine cDNA, the nucleotide sequence and the corresponding deduced amino acid sequences were 82% and 86% identical to the respective human sequences. All five amino acids presently known to be essential for normal enzymatic activity were conserved between mouse and man. The murine enzyme had a single deletion relative to the human enzyme at amino acid number 273. One ATG translation initiation signal was present in the mouse sequence in contrast to the human sequence, where two start codons have been reported. Nucleotide sequencing of a clone derived from murine genomic DNA revealed that the murine signal for translation initiation was located in exon 2. The locations of all 10 introns were conserved among mouse and man. We mapped the genetic locus for glucocerebrosidase to mouse chromosome 3, at a position 7.6 ± 3.2 centimorgans from the locus for the β subunit of nerve growth factor. Comparison of linkage relationships in the human and murine genome indicates that these closely linked mouse genes are also syntenic on human chromosome 1 but in positions that span the centromere.