COMPLEXITY AND CONTENT OF THE DNA AND RNA IN TRYPANOSOMA-CRUZI

作     者：LANAR, DE LEVY, LS MANNING, JE 

作者机构：UNIV CALIF IRVINE DEPT DEV & CELL BIOL IRVINE CA 92717 USA 

出 版 物：《MOLECULAR AND BIOCHEMICAL PARASITOLOGY》 (分子与生化寄生虫学)

年 卷 期：1981年第3卷第5期

页      面：327-341页

核心收录：

学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 1001[医学-基础医学(可授医学、理学学位)] 07[理学] 

基　　金：NCI NIH HHS [CA00522] Funding Source: Medline NIGMS NIH HHS [GM 22207] Funding Source: Medline 

主　　题：Trypanosoma cruzi RNA DNA Reassociation kinetics Sequence complexity C o t R o t initial DNA or RNA concentration in mol nucleotides × time (s). kb, kilobases, 1000 nucleotides or nucleotide pairs for single- and double-stranded DNA, respectively NT nucleotides NTP nucleotide pairs RMS root mean square poly(A) + -RNA polyadenylated RNA poly(A) − -RNA non-polyadenylated RNA FCS fetal calf serum 

摘      要：The content and sequence complexity of the nuclear DNA and messenger RNA for epimastigotes of T. cruzi were determined. From analysis of nuclear DNA reassociation studies and microspectrofluorometric measurements of laser induced fluorescence of cellular DNA, T. cruzi is found to be a diploid organism with a nuclear DNA content of 2.5 .times. 108 nucleotide pairs (2.8 .times. 10-13 g) and a kinetoplast DNA content of 4.9 .times. 107 nucleotide pairs (5.4 .times. 10-14 g). Reassociation kinetics of nuclear DNA of average length of 0.4 kb reveals 3 kinetic components: a moderately repetitive component with a reiteration frequency of 5.1 .times. 103 present in 9% of the fragments, a lowly repetitive component with a reiteration frequency of 32 present in 51% of the fragments and a single-copy component present in 23% of the fragments. By saturation hybridization of total polysomal RNA to 3H-labeled single-copy DNA, it was determined that 68% of the single-copy DNA was represented in the epimastigote polysomal RNA. This corresponds to .apprx. 12,000 different mRNA species. Of these, .apprx. 9000 are present as poly(A)+-RNA;the remaining 3000 appear not to be polyadenylated. Kinetic analysis of the poly(A)+-RNA population indicates it is composed of at least 3 classes of RNAs of different abundancy levels: 2 sequences which occur .apprx. 3000 times per cell, .apprx. 750 sequences which occur about 20 times per cell and .apprx. 15,500 sequences which occur 1-2 times per cell.