David MacLennan
David Herman MacLennan ( born July 3, 1937 in Swan River, Manitoba ) is a Canadian biochemist and molecular biologist who deals with membrane transport and molecular biology of membrane proteins.
MacLennan made 1959 his bachelor's degree in Agricultural Science at the University of Manitoba. In 1961 he received his master's degree in plant pathology at Purdue University, where he became in 1963 a doctorate in biology. He then worked as a post-doctoral researcher and since 1964 as an Assistant Professor at the University of Wisconsin in the Institute for Enzyme Research. In 1969 he became Associate Professor in 1974 and Professor in the Banting and Best Department of Medical Research of the University of Toronto, which he headed from 1978 to 1990. Since 1987 he has been there JW Bille Professor of Medical Research and University Professor since 1993.
It is known for fundamental studies on the regulation of calcium transport across the sarcoplasmic reticulum ( SR ) of the muscle cells, the mechanism of the calcium pumps in the membrane of the SR, the storage of calcium in the SR, and the release of calcium by special membrane channels. The ATP-dependent calcium pump of the SR he studied since 1969, after he had initially researched electron transport and proton pumps in mitochondria. As in the mitochondria ATPase was also involved in the calcium pump in SR, but in contrast to the mitochondria also takes over the ion transport as MacLennon 1969 proved.
He examined mutations and abnormal variations in the proteins involved and the diseases caused by it. For example, he showed that mutations in phospholamban, which regulates the work of the calcium pump, can lead to cardiomyopathy and he discovered the role of a mutation of the channels for calcium release as a cause of stress syndrome in pigs, followed by an appropriate diagnostic test could be developed, what the occurrence of the syndrome greatly reduced. He was with his staff the causes of malignant hyperthermia, the central core myopathy and Brody syndrome, in which the absorption of calcium in the SR is reduced by a contraction due to a defective enzyme, which prevents the relaxation of muscles after physical exertion and cramps leads.
1972 to 1976 he was editor of the Canadian Journal of Biochemistry.