Abstract
Electrophoretic and activity variants for a liver aldehyde reductase (AHR-A2) among strains of Mus musculus have been used in genetic analyses to demonstrate close linkage between the locus encoding this enzyme (designated Ahr-1) and the alcohol dehydrogenase gene complex on chromosome 3. No recombinants were observed between Adh-3 (encoding alcohol dehydrogenase C2; ADH-C2) and Ahr-1 among 42 backcross animals. Moreover, linkage disequilibrium between these loci was observed among 58 of 60 strains of mice examined and among seven recombinant inbred strains derived from C57BL/6J and BALB/c mice. Liver hexonate dehydrogenase (HDH-A) was electrophoretically invariant among the strains examined. Gel filtration analyses demonstrated that AHR-A2 and HDH-A had native molecular weights of approximately 80,000 and 32,000, respectively. Three-banded allozyme patterns for AHR-A2 in CBA/H x castaneus hybrid animals were consistent with a dimeric subunit structure. Comparative substrate and coenzyme specificities for AHR-A2, HDH-A, and ADH-A2 (liver ADH isozyme) were examined. AHR-A2 exhibited a defined specificity toward p-nitrobenzaldehyde as substrate, whereas the other enzymes exhibited broad specificities toward various aliphatic, aromatic, and monosaccharide aldehydes. It is proposed that Ahr-1 is a product of a gene duplication event during mammalian evolution of the primordial mammalian Adh locus and that considerable divergence in catalytic properties has subsequently occurred.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.