Inactivity of recombinant ELA2B provides a new example of evolutionary elastase silencing in humans.

ABSTRACT:

Background

The archetypal mammalian elastase (ELA1) is not expressed in the human pancreas, because evolutionary mutations suppressed transcription of the ELA1 gene.

Aims

In this study, we tested the theory that the unique duplication of the ELA2 gene in humans might compensate for the loss of ELA1.

Methods

Recombinant ELA2A and ELA2B were expressed in Escherichia coli, and their activity was tested on Glt-Ala-Ala-Pro-Leu-p-nitroanilide, DQ elastin and bovine milk protein.

Results

Surprisingly, recombinant ELA2B was completely devoid of proteolytic activity, while ELA2A readily hydrolyzed all three test substrates. Furthermore, ELA2A formed an SDS-resistant complex with alpha1-antitrypsin, whereas ELA2B did not bind covalently to the inhibitor. Finally, chimera

SUBMITTER: Szepessy E 

PROVIDER: S-EPMC1447606 | biostudies-literature | 2006

REPOSITORIES: biostudies-literature