%0 Journal Article %A Toffaletti, Dena L. %A Del Poeta, Maurizio %A Rude, Thomas H. %A Dietrich, Fred %A Perfect, John R. %T Regulation of cytochrome c oxidase subunit 1 (COX1) expression in Cryptococcus neoformans by temperature and host environment %D 2003 %J Microbiology, %V 149 %N 4 %P 1041-1049 %@ 1465-2080 %R https://doi.org/10.1099/mic.0.26021-0 %I Microbiology Society, %X In the study of differential gene expression of Cryptococcus neoformans, a transcript of COX1 (cytochrome oxidase c subunit 1) was identified in a serotype A strain. The transcript was upregulated at 37 °C compared to 30 °C and expressed by yeasts infecting the central nervous system. Northern analysis of COX1 from the serotype A strain revealed two polycistronic transcripts, a temperature-upregulated 2·3 kb transcript and a 1·9 kb transcript that was not affected by temperature. In contrast, COX1 in a serotype D strain showed only a 1·9 kb polycistronic transcript plus a 1·6 kb monocistronic message, and temperature had no effect on the transcripts. The sequence of COX1 revealed similar coding regions between the two strains, but the serotype D strain had five introns whereas no introns were found in the serotype A strain. The serotype D strain had reduced growth rates compared to the serotype A strain at 37 °C, but in an AD hybrid strain the serotype D COX1 gene could support efficient high temperature growth. These studies have revealed mitochondrial molecular differences between serotype A and D strains which show evolutionary divergence. It will be important to determine whether differences in mitochondrial structure and function can influence cryptococcosis. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.26021-0