MOLECULAR-CLONING AND DEDUCED AMINO-ACID-SEQUENCES OF THE GAMMA-SUBUNITS OF RAT AND MONKEY NAD(-ISOCITRATE DEHYDROGENASES())

A 600 bp cDNA fragment encoding part of the gamma-subunit of pig heart NAD+-isocitrate dehydrogenase (ICDHgamma) was amplified by PCR using redundant oligonucleotide primers based on partial peptide sequence da ta [Huang and Colman (1990) Biochemistry 29, 8266-8273]. This PCR frag ment was then used as a probe to isolate clones encoding the complete mature forms of the gamma-subunit from rat epididymis and monkey testi s cDNA libraries. Comparison of the deduced amino acid sequences of th e rat and monkey subunits and the partial sequence of the pig heart en zyme revealed a remarkably high level of sequence identity. The relati onship between the deduced amino acid sequences of the NAD+-ICDH gamma -subunits and those of non-mammalian NAD+- and NADP+-ICDH subunits is discussed.