Volume 272, Number 14,
Issue of April 4, 1997
pp. 9524-9530
©1997 by The American Society for Biochemistry and Molecular Biology, Inc.
Expression and Regulation of the Human and Mouse
Aspartylglucosaminidase Gene
(Received for publication, October 18, 1996, and in revised form, January 8, 1997)
Annukka
Uusitalo
,
Kai
Tenhunen
,
Jukka
Tenhunen
§
,
Sampsa
Matikainen
¶
,
Leena
Peltonen
and
Anu
Jalanko
From the Departments of Human Molecular Genetics and
¶ Virology, National Public Health Institute, FIN-00300 Helsinki,
Finland and the § Orion Corporation, Orion Pharma, FIN-00700
Helsinki, Finland
Aspartylglucosaminidase (AGA) is a lysosomal
enzyme that catalyzes one of the final steps in the degradation of
N-linked glycoproteins. Here we have analyzed the
tissue-specific expression and regulation of the human and mouse AGA
genes. We isolated and characterized human and mouse AGA 5
-flanking
sequences including the promoter regions. Primer extension assay
revealed multiple transcription start sites in both genes,
characteristic of a housekeeping gene. The cross-species comparison
studies pinpointed an approximately 450-base pair (bp) homologous
region in the distal promoter. In the functional analysis of human AGA
5
sequence, the critical promoter region was defined, and an
additional upstream region of 181 bp exhibiting an inhibitory effect on
transcription was identified. Footprinting and gel shift assays
indicated protein binding to the core promoter region consisting of two
Sp1 binding sites, which were sufficient to produce basal promoter
activity in the functional studies. The results also suggested the
binding of a previously uncharacterized transcription factor to a 23-bp stretch in the inhibitory region.