Biomaterial Database

Hemoglobin switching in sheep and goats. Preparation and characterization of complementary DNAs specific for the alpha-, beta-, and gamma-globin messenger RNAs of sheep. 1977

E J Benz, and C E Geist, and A W Steggles, and J E Barker, and A W Nienhuis

Specific complementary DNAs (cDNAs) for the messenger RNAs coding for sheep alpha-, betaA-, betaB-, betaC-, and gamma-globins were prepared by thermal denaturation of heterologous hybrids (e.g. alphabetaB-cDNA-alphagamma-mRNA) followed by hydroxylapatite chromatography. Each cDNA represented a nearly full-length copy of its globin mRNA complement as determined by electrophoretic analysis in polyacrylamide gels containing 98% formamide. The purity of each cDNA fraction was estimated by hybridization analysis and thermal denaturation. The beta- and gamma-cDNAs contained 5 to 20% contaminating alpha-cDNA while the alpha-cDNA was 25 to 30% contaminated with non-alpha-cDNA. The melting temperatures (Tm) of homologous duplexes between each non-alpha chain cDNA and its mRNA complement ranged from 69.5-71.5 degrees in 50% formamide while alpha-alpha duplexes melted with a Tm of 75-76 degrees. The Tm values of heterologous duplexes formed between each non-alpha-cDNA and the various globin mRNAs (e.g. betaB-cDNA-Hb C mRNA) ranged between 64.5 degrees and 68 degrees and thus were only 1.5-5.0degrees below that of homologous duplexes. These results suggest that the nucleotide sequence divergence among the various non-alpha-mRNAs (or cDNAs) is not greatly different from the minimum predicted from the amino acid sequence differences of the corresponding globins. When annealing reactions were performed above the Tm of the heterologous hybrids (68 degrees), each non-alpha-cDNA hybridized only to its own complementary mRNA. Thus the purified cDNAs provide molecular probes for the quantitation of alpha-, beta-, and gamma-globin-specific nucleotide sequences.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009691	Nucleic Acid Denaturation	Disruption of the secondary structure of nucleic acids by heat, extreme pH or chemical treatment. Double strand DNA is "melted" by dissociation of the non-covalent hydrogen bonds and hydrophobic interactions. Denatured DNA appears to be a single-stranded flexible structure. The effects of denaturation on RNA are similar though less pronounced and largely reversible.	DNA Denaturation,DNA Melting,RNA Denaturation,Acid Denaturation, Nucleic,Denaturation, DNA,Denaturation, Nucleic Acid,Denaturation, RNA,Nucleic Acid Denaturations
D009693	Nucleic Acid Hybridization	Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)	Genomic Hybridization,Acid Hybridization, Nucleic,Acid Hybridizations, Nucleic,Genomic Hybridizations,Hybridization, Genomic,Hybridization, Nucleic Acid,Hybridizations, Genomic,Hybridizations, Nucleic Acid,Nucleic Acid Hybridizations
D012156	Reticulocytes	Immature ERYTHROCYTES. In humans, these are ERYTHROID CELLS that have just undergone extrusion of their CELL NUCLEUS. They still contain some organelles that gradually decrease in number as the cells mature. RIBOSOMES are last to disappear. Certain staining techniques cause components of the ribosomes to precipitate into characteristic "reticulum" (not the same as the ENDOPLASMIC RETICULUM), hence the name reticulocytes.	Reticulocyte
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D005914	Globins	A superfamily of proteins containing the globin fold which is composed of 6-8 alpha helices arranged in a characterstic HEME enclosing structure.	Globin
D006041	Goats	Any of numerous agile, hollow-horned RUMINANTS of the genus Capra, in the family Bovidae, closely related to the SHEEP.	Capra,Capras,Goat
D006454	Hemoglobins	The oxygen-carrying proteins of ERYTHROCYTES. They are found in all vertebrates and some invertebrates. The number of globin subunits in the hemoglobin quaternary structure differs between species. Structures range from monomeric to a variety of multimeric arrangements.	Eryhem,Ferrous Hemoglobin,Hemoglobin,Hemoglobin, Ferrous
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA