Cloning and Expression of Murine Hsp40 Gene: Differences in Initiation Sites Between Heat-Induced and Constitutive Transcripts

Abstract

We have isolated cDNA and genomic clones of murine Hsp40 (mmDjB1). The murine Hsp40 gene was expressed at a high level in testis and was induced by heat shock. The transcriptional initiation sites were different between heat-induced transcripts and constitutive ones. The heat-induced transcripts initiated 22 to 28 bp downstream of the TATA box, whereas constitutive transcripts initiated from multiple sites, many of which initiated upstream of the TATA box. To our knowledge, this is the first report on the heat shock-dependent usage of transcriptional start sites of a heat shock gene.

Key Words:

• Murine Hsp40 (mmDjBl)
• Transcriptional initiation