Multiple forms of cyclic nucleotide phosphotransferases in mouse thymocytes
Rybalkin, S.D.; Kurennaia, G.S.; Sobolev, A.S.
Biokhimiia 49(12): 1927-1933
1984
ISSN/ISBN: 0320-9725 PMID: 6098315 Document Number: 228747
The presence of cAMP- and cGMP- specific phosphodiesterases in mouse thymocytes has been demonstrated. Sucrose density gradient centrifugation revealed two peaks corresponding to cAMP-phosphodiesterase (3.6S and 6.0S) and one peak corresponding to cGMP-phosphodiesterase (6.6S). Gel filtration demonstrated high molecular forms of the enzymes; according to the rechromatography data, cAMP and cGMP phosphodiesterases are represented by oligomers containing subunits with Ms 45 000 and 160 000 respectively. Incubation of thymocyte lysates for 24-48 hours led to a decrease of the number of high molecular weight forms and an increase in the number of low molecular weight forms paralleled with a rise in V and Km values.