Measurement of the complexity and diversity of poly(adenylic acid) containing messenger RNA from rat liver.
The complexity of rat liver poly (A)+ messenger RNA (mRNA) has been measured by analysis of the kinetics of hydridization with both complementary DNA (cDNA) and single copy DNA. The complementary DNA-poly(A)+ mRNA hybridization reaction demonstrates the existence of three abundance classes representing 18, 37, and 45% of the cDNA and 4, 290, and 24 000 different 1800-nucleotide sequences respectively. The poly(A)+ mRNA driven single copy DNA hybridization reaction reveals a single major transition accounting for 1.9% of the haploid rat genome. The kinetics of the poly(A)+ mRNA driven single copy DNA reaction suggest that approximately 45% of the mass of the mRNA population contains over 95% of the complexity. Although higher than previous estimates, the base sequence complexities of rat liver poly(A)+ mRNA measured in these two ways are in good agreement, suggesting that the technique of poly(A)+ mRNA-cDNA hybridization may be used in approximating the complexity as well as abundance of a messenger RNA population. DNA-driven cDNA reactions reveal that about 10% of rat liver poly(A)+ mRNA is transcribed from repetitive sequences in the rat genome.
D000818:Animals; D007700:Kinetics; D008099:Liver / Q000032:analysis*; D009693:Nucleic Acid Hybridization; D011061:Poly A / Q000032:analysis*; D011132:Polyribosomes / Q000032:analysis; D012333:RNA, Messenger / Q000302:isolation & purification; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism; D051381:Rats; D013698:Templates, Genetic
D012333:RNA, Messenger; D011061:Poly A; D012194:RNA-Directed DNA Polymerase