Contents - Medicinski Fakultet u Sarajevu - University of Sarajevo

Oral presentationEVALUTATION OF OXIGEN CONSUPTION OF HYBRIDE CLONESWITH POINT MUTATION ON tRNA ser(UCN) OF MITOCHONDRIALDNAEmina Kiseljaković 1 , Sabaheta Hasić 1 , Radivoj Jadrić 1 , Zakira Mornjaković 2 ,Mira Winterhalter-Jadrić 11Department of Biochemistry,Medical Faculty, Sarajevo,Bosnia and Herzegovina2Institute of Histology,Medical Faculty, Sarajevo,Bosnia and HerzegovinaE-mail: eminacengic@hotmail.comIntroduction: Point mutations in tRNA of mtDNA arecause of defects in oxidative phosphorilation processand decrease in adenosine triphosphate synthesis thatis a major source of energy for cellular function.Objectives: To determine possible defect of function ofrespiratory chain.Material and Kethods: We analyzed a hybrid clonescells derived from two patients with apparently homoplasmatic,pathogenic point mutation on 7497 and7512 tRNA ser(UCN) of mtDNA. Activity of complexes I, IIand III was determined by polarographic oxygen consumptionmeasurement. The endogenous substrate andadded substrates respiration rate of hybrid clones cellswith mutation and 143B control cells was recorded usingClark Oxygen electrodes.Results: Comparing respiration rates of endogenoussubstrate and added substrates in hybrids with mutationand control cells we have got an evidence for complexI deficiency. Results are expressed as mean values± SD.Conclusion: Polarographic measurement of oxygenconsumption is sensitive method. Usage of differentsubstrates allows determination of respiratory chainfunction presence and precise designation which enzymecomplex has a low activity.Key words: mitochondrial tRNA ser(UCN) , point mutation,oxygen consumption measurement.27