Biomaterial Database

Histone formation, gene expression, and zinc deficiency in Euglena gracilis. 1984

B Mazus, and K H Falchuk, and B L Vallee

Histones, and other basic proteins, have been isolated from zinc-sufficient (+Zn) Euglena gracilis by standard chromatographic methods. These cells contain 2.46 micrograms of histones and 1.96 micrograms of DNA per 10(6) organisms. Each of the histones, H1, H3, H2A, H2B, and H4, is present in both log- and stationary-phase +Zn cells and has been characterized according to its electrophoretic mobility and molecular weight. H1 has been further identified on the basis of its amino acid composition and its cross-reactivity with calf thymus histone H1 antibodies. Similarly, H3 has been recognized as well by its specific reaction with an H3 antibody. In contrast, log-phase zinc-deficient (-Zn) cells contain H1 and H3 while H2A, H2B, and H4 are absent. All of the histones vanish in stationary-phase-Zn organisms. The DNA content increases as the -Zn cells progress from log to stationary phase, reaching a value of 4.40 micrograms/10(6) cells, double that of comparable stationary-phase +Zn organisms. A 2000-3000-dalton polypeptide whose electrophoretic behavior differs from that of the known histones constitutes over 90% of the total basic proteins of -Zn cells. On addition of zinc to stationary -Zn cells, cell division resumes, and all the histones and other basic proteins reappear. Together with previous results, the data demonstrate that zinc significantly affects the metabolism of all major chromatin components, i.e., the RNA polymerases, DNA, and histones of E. gracilis [Vallee, B.L., & Falchuk, K.H. (1981) Philos. Trans. R. Soc. London, Ser. B 294, 185-197]. The implications of these effects of zinc on chromatin structure and function are discussed.

UI	MeSH Term	Description	Entries
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
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
D005056	Euglena gracilis	A species of fresh-water, flagellated EUKARYOTES in the phylum EUGLENIDA.	Euglena gracili,gracilis, Euglena
D005796	Genes	A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.	Cistron,Gene,Genetic Materials,Cistrons,Genetic Material,Material, Genetic,Materials, Genetic
D006657	Histones	Small chromosomal proteins (approx 12-20 kD) possessing an open, unfolded structure and attached to the DNA in cell nuclei by ionic linkages. Classification into the various types (designated histone I, histone II, etc.) is based on the relative amounts of arginine and lysine in each.	Histone,Histone H1,Histone H1(s),Histone H2a,Histone H2b,Histone H3,Histone H3.3,Histone H4,Histone H5,Histone H7
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
D013950	Thymus Gland	A single, unpaired primary lymphoid organ situated in the MEDIASTINUM, extending superiorly into the neck to the lower edge of the THYROID GLAND and inferiorly to the fourth costal cartilage. It is necessary for normal development of immunologic function early in life. By puberty, it begins to involute and much of the tissue is replaced by fat.	Thymus,Gland, Thymus,Glands, Thymus,Thymus Glands
D015032	Zinc	A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.