edgepedia

All articles A–Z

519,064 articles

Histone acetyltransferase GCN5

KAT2A, also called GCN5, is a GNAT-family lysine acetyltransferase and the catalytic KAT of SAGA and ATAC complexes, acetylating H3K9/H3K14 and acting as a histone succinyltransferase linked to cancer and HBV.

Histone acetyltransferases subunit 3

Histone acetyltransferases subunit 3, or ADA3 (alteration/deficiency in activation 3), is a conserved non-catalytic subunit of GCN5-containing HAT complexes (ADA, SAGA, ATAC, STAGA, TFTC) required for nucleosomal acetylation, p53 acetylation, cell cycle control, and genome stability.

Histone deacetylase

Histone deacetylases (HDACs), also called lysine deacetylases, are 18 human enzymes in four classes (zinc-dependent classes I, II, IV; NAD+-dependent sirtuins, class III) that remove acetyl groups from histone and nonhistone proteins; their inhibitors, such as vorinostat and romidepsin, are approved anticancer drugs.

Histone deacetylase inhibitor

Histone deacetylase (HDAC) inhibitors are epigenetic drugs that block zinc-dependent HDAC enzymes, increasing histone acetylation; four (vorinostat, belinostat, romidepsin, panobinostat) are FDA-approved mainly for lymphoma and myeloma.

Histone H1-like protein Hct1

Histone H1-like protein Hc1 (hctA, CT_743, UniProt P0CE15) is an 18-kDa, 125-amino-acid DNA-binding protein of Chlamydia trachomatis elementary bodies that condenses chromatin, represses transcription and translation, and is regulated by IspE and the sRNA IhtA.

Histone H2A

Histone H2A, a core histone forming H2A-H2B dimers in nucleosomes, has the largest variant family among core histones, including H2A.Z, H2A.X, H2A.B, and macroH2A, which specialize transcription, DNA repair, and chromatin stability.

Histone H2B

Histone H2B, a core nucleosome protein (two H2A-H2B dimers per octamer, ~147 bp DNA), with 22 human genes, germline variants H2B.1/L/W/K/N, H2BK120ubiquitination, and cancer mutations such as E76K.

Histone H4

Histone H4 is a core histone that pairs with H3 in the nucleosome's central tetramer. Extremely conserved from yeast to humans, essentially variant-free except H4.G, with an N-terminal tail whose acetylation and K20 methylation regulate chromatin packing and DNA repair.

Histone methylation

Histone methylation: addition of methyl groups to histone lysine or arginine residues, a reversible epigenetic mark written by KMTs/PRMTs, erased by demethylases, and read by methyl-lysine-binding domains; H3K4/H3K36/H3K79 mark active transcription, H3K9/H3K27/H4K20 repression; EZH2 inhibitors tazemetostat and valemetostat are approved cancer drugs.

Histone mRNA 3′ end processing

Histone mRNA 3′ end processing is the pathway that gives replication-dependent histone mRNAs their stem-loop 3′ ends through a single cut directed by the U7 snRNP, with no poly(A) tail added.

Histone-lysine N-methyltransferase

Histone-lysine N-methyltransferases (HKMTs, KMTs), e.g., SUV39H1, EZH2, DOT1L, G9a: SAM-dependent enzymes methylating histone lysines (H3K4, K9, K27, K36, K79, H4K20) to regulate gene expression; SET-domain or DOT1L classes, targeted by inhibitors such as tazemetostat.

Histopathology

Histopathology, or histopathological examination, is the branch of pathology that diagnoses disease by examining stained tissue samples under a microscope, the gold standard for cancer, inflammation, and infection.

Histoplasma

Histoplasma, notably Histoplasma capsulatum, is a thermally dimorphic soil fungus causing histoplasmosis, concentrated in the Ohio and Mississippi River Valleys; inhaled microconidia convert to yeast at 37 °C, with antigen testing guiding diagnosis.

Histoplasmosis

Histoplasmosis, caused by the dimorphic fungus Histoplasma capsulatum, is a pneumonia acquired by inhaling spores from soil enriched with bird or bat droppings; endemic in the Ohio and Mississippi River Valleys, treated with amphotericin B or itraconazole.

Histoplasmosis due to Histoplasma duboisii

African histoplasmosis, infection by Histoplasma capsulatum var. duboisii (H. duboisii), endemic to central and western Africa; causes skin, bone, and lymph node lesions with large 6-12 µm yeasts, unlike pulmonary classical histoplasmosis.

Historia antigua de México

Historia antigua de México is a history of prehispanic Mexico written by the exiled Jesuit Francisco Javier Clavijero and first published in Italian in 1780.

Historia Brittonum

Historia Brittonum ("History of the Britons") is a ninth-century Cambro-Latin history of Britain, written in Gwynedd c. 829/30, traditionally but doubtfully attributed to Nennius, containing the earliest securely datable Arthur references.

Historia de Belgrano y de la independencia argentina

Historia de Belgrano y de la independencia argentina is an 1858 history by Bartolomé Mitre that narrates Manuel Belgrano's life and the emergence of Argentina as an independent nation.

Historia de la conquista de México

Historia de la conquista de México is a 1552 chronicle by Francisco López de Gómara, detailing the conquest of the Aztec Empire and serving as an influential early account.

Historia de la eternidad

Historia de la eternidad is a 1936 book of essays by the Argentine writer Jorge Luis Borges, first published in Buenos Aires and expanded in 1953.

Historia de la Nueva México

Historia de la Nueva México is a 1610 Spanish epic poem by Gaspar Pérez de Villagrá narrating Juan de Oñate's 1598 expedition into New Mexico.

Historia de las Indias

Historia de las Indias is a three-part history of the Spanish Indies by Bartolomé de las Casas, left unpublished at his death and first printed in Madrid in 1875.

Historia de las Indias de Nueva España e islas de tierra firme

A sixteenth-century chronicle by the Dominican friar Diego Durán recounting the history and religion of the Aztecs of central Mexico, rediscovered in the nineteenth century.

Historia de los indios de la Nueva España

Historia de los indios de la Nueva España (History of the Indians of New Spain) is a sixteenth-century chronicle by the Franciscan missionary Motolinía on Mexico's Indigenous peoples.

Historia de México

Historia de México, published as Historia de Méjico, is a five-volume history of Mexico by the statesman and historian Lucas Alamán, published in Mexico City between 1849 and 1852.

Historia de San Martín y de la emancipación sudamericana

Historia de San Martín y de la emancipación sudamericana is an 1887 three-volume biography of José de San Martín by Bartolomé Mitre, the foundational Argentine account of the liberator.

Historia de Tlaxcala

Historia de Tlaxcala is a colonial chronicle of Tlaxcala by the mestizo historian Diego Muñoz Camargo, written between 1576 and 1591 and dedicated to Philip II.

Historia de una pasión argentina

Historia de una pasión argentina is a 1937 autobiographical essay by Eduardo Mallea, published by editorial Sur in Buenos Aires and regarded as his most important essay.

Historia de Yucatán

Historia de Yucatán is a history of the Yucatán Peninsula by the Spanish Franciscan friar Diego López de Cogolludo, published posthumously in Madrid in 1688.

Historia del descubrimiento y conquista del Perú

Historia del descubrimiento y conquista del Perú is a sixteenth-century Spanish chronicle by Agustín de Zárate, first printed in Antwerp in 1555, covering Peru's conquest and Inca empire.