Kinetic and structural characterization of an alternatively spliced variant of human mitochondrial 5'(3')-deoxyribonucleotidase

0435125 - ÚMG 2015 RIV GB eng J - Journal Article
Pachl, Petr - Fábry, Milan - Veverka, Václav - Brynda, Jiří - Řezáčová, Pavlína
Kinetic and structural characterization of an alternatively spliced variant of human mitochondrial 5'(3')-deoxyribonucleotidase.
Journal of Enzyme Inhibition and Medicinal Chemistry. Roč. 30, č. 1 (2015), 63-68. ISSN 1475-6366. E-ISSN 1475-6374
R&D Projects: GA ČR GA203/09/0820; GA MŠMT(CZ) LK11205
Institutional support: RVO:61388963 ; RVO:68378050
Keywords : 5'(3')-deoxyribonucleotidase * alternative splicing * crystal structure * hydrolase * mitochondria
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 3.428, year: 2015

Abstract Human mitochondrial 5'(3')-deoxyribonucleotidase (mdN) catalyzes dephosphorylation of nucleoside monophosphates, and thus helps maintain homeostasis of deoxynucleosides required for mitochondrial DNA synthesis. Mature mdN is a 23-kDa dimeric protein with highest expression levels in the heart, brain and skeletal muscle. We have identified an alternative splice variant of the mdN gene containing an 18-nucleotide insertion encoding 6 amino acids (GKWPAT) at the 3'-end of the penultimate exon 4. We recombinantly expressed this enzyme variant and characterized its biochemical and kinetic properties as well as its three-dimensional structure. Our high-resolution (1.27 Å) crystal structure revealed that the insertion forms a loop located in the vicinity of the active site pocket and affects enzyme kinetic parameters as well as protein thermal stability.
Permanent Link: http://hdl.handle.net/11104/0241979