AN IMPROVED METHOD FOR ISOLATING RNA FROM COCCIDIAN OOCYSTS

A method, based on the disruption of eimerian oocysts in a French pres sure cell in the presence of guanidine isothiocyanate, has been develo ped to isolate large quantities of high quality total RNA efficiently. This procedure results in a 12.5-fold greater number of oocysts broke n, and a 22-fold greater yield of total RNA than from disruption by co nventional grinding in liquid N-2. In addition, the RNA isolated by th e French pressure cell method was of equal or superior quality when co mpared to RNA isolated by grinding. This procedure provides a signific ant improvement in RNA extraction from eimerian oocysts and will great ly facilitate the study of gene expression in this important group of parasites.