RNA and gene regulation

FTO gene

FTO (fat mass and obesity-associated gene), also called the FTO obesity locus on chromosome 16, was the first GWAS-identified obesity gene (2007) and encodes the first known m6A RNA demethylase; its common risk alleles raise BMI by 0.39 kg/m2 per copy but do not block weight loss.

Full-length cDNA sequencing

Full-length cDNA sequencing is a transcriptomic method that copies complete messenger RNA molecules into DNA and sequences each end to end, revealing isoforms, splice sites, and gene fusions.

Full-length transcriptome sequencing

Full-length transcriptome sequencing reads entire RNA transcript molecules end to end on long-read platforms such as PacBio Iso-Seq and Oxford Nanopore, determining complete isoform sequences directly.

G protein pathway suppressor 2

GPS2 (G protein pathway suppressor 2), also AMF-1, a 327-aa human corepressor protein in the NCoR/SMRT/HDAC3 complex at 17p13.1, with anti-inflammatory JNK-inhibiting and metabolic roles.

G-quadruplex

G-quadruplex (G4), four-stranded nucleic acid structure from guanine-rich DNA or RNA, built of stacked G-tetrads stabilized by K+ or Na+. Found at telomeres and promoters; regulates transcription and is targeted by anticancer drugs CX-5461 and QN-302.

GAS5

GAS5 (growth arrest specific 5, SNHG2) is a human long non-coding RNA gene at 1q25.1 that hosts snoRNAs, decoys the glucocorticoid receptor via a GRE mimic, and acts as a tumor suppressor downregulated in many cancers.

GATA1

GATA1 (GATA binding protein 1, ERYF1, NF-E1) is an X-linked zinc finger transcription factor binding (A/T)GATA(A/G) motifs that master-regulates erythroid and megakaryocytic differentiation; its GATA1s truncation causes Down syndrome leukemias and dyserythropoietic anemia.

GATA2

GATA2 (GATA binding protein 2) is a zinc-finger transcription factor gene essential for hematopoietic stem cell maintenance; germline mutations cause GATA2 deficiency syndrome (MonoMAC, DCML, Emberger) with MDS/AML and immunodeficiency.

Gene expression profiling

Gene expression profiling, also known as expression profiling, is a molecular biology method that measures mRNA levels of many genes at once, using microarrays or RNA sequencing.

Gene knockdown

Gene knockdown is a set of laboratory techniques that reduce a specific gene's expression without altering its DNA sequence, most commonly through RNA interference or antisense oligonucleotides.

Gene silencing

Gene silencing: suppression of gene expression at transcriptional (TGS) or post-transcriptional (PTGS) levels without altering DNA. Includes RNAi, antisense, quelling, chromatin silencing; discovered in plants around 1990, mechanistically explained by RNA interference.

General transcription factor

A general transcription factor, also called a basal transcription factor, is a protein required to initiate transcription by RNA polymerase II at essentially all protein-coding promoters.

General transcription factors in disease and therapy

General transcription factors in disease and therapy covers congenital transcription syndromes from TFIIH and BRF2 mutations, cancer-linked alterations in the basal machinery, and emerging therapies targeting transcription factors.

Genomic organization of snoRNA loci

The genomic organization of snoRNA loci covers how small nucleolar RNA genes are arranged, mostly within host-gene introns in vertebrates or as independent transcription units in yeast.

Glucitol operon activator

The glucitol operon activator, usually called GutM, is a small transcriptional activator protein in Escherichia coli that positively regulates the gut operon, the gene cluster that transports and metabolizes the sugar glucitol.

Glucocorticoid receptor

Glucocorticoid receptor (GR, NR3C1), a ligand-activated nuclear receptor for cortisol; three-domain structure, multiple splice isoforms, regulates up to 20% of the genome via GREs, nGREs, and NF-κB/AP-1 transrepression; target of selective modulators.

Glutamine-tRNA synthetase

Glutaminyl-tRNA synthetase (GlnRS, EC 6.1.1.18), a class I aminoacyl-tRNA synthetase, charges tRNA^Gln with glutamine via a glutaminyl-adenylate intermediate; absent from most bacteria and all archaea, which use a transamidation pathway.

Glutamyl-tRNA synthetase

Glutamyl-tRNA synthetase (GluRS) is a class I aminoacyl-tRNA synthetase that attaches glutamate to tRNA during protein synthesis. Some non-discriminating forms also charge tRNA^Gln, feeding the ancient transamidation pathway.

Glycine-tRNA ligase, beta subunit

Beta subunit of bacterial α2β2 glycyl-tRNA synthetase: ~65 kDa chain carrying tRNA recognition elements, encoded with the 303-codon alpha chain on one E. coli mRNA, evolutionarily derived from alanyl-tRNA synthetase.

GRIA2 Q/R site editing

GRIA2 Q/R site editing: ADAR2-mediated A-to-I RNA editing converting GluA2 (GluR2) codon 607 from glutamine to arginine, making AMPA receptors calcium-impermeable; nearly 100% edited in adult brain and essential for survival.

Group II intron

Group II intron: self-splicing mobile ribozyme with an intron-encoded reverse transcriptase, found in bacteria and organelles, subgrouped IIA/IIB/IIC, and the likely ancestor of spliceosomal introns and retrotransposons.

Growth-regulating factor

Growth-regulating factors (GRFs) are streptophyte-specific plant transcription factors with QLQ and WRC domains, forming the GRF-GIF-miR396 growth module; not the rose nursery GRF or growth hormone-releasing factor.

Guide RNA

Guide RNA (gRNA): a small RNA that base pairs with a target nucleic acid to direct a protein activity there; term coined by Blum et al. 1990 for trypanosome RNA editing, now central to snoRNAs, siRNA/miRNA silencing, and CRISPR sgRNA/pegRNA genome editing.

H/ACA box snoRNAs

H/ACA box snoRNAs are small non-coding RNAs with a conserved two-hairpin structure that guide pseudouridylation of ribosomal RNA and snRNAs, working with the pseudouridine synthase dyskerin; humans have 190.

H/ACA ribonucleoprotein complex, subunit Gar1/Naf1

Gar1/Naf1 domain family of box H/ACA ribonucleoproteins: Gar1 is a mature RNP core subunit and Naf1 an assembly factor; both bind the pseudouridine synthase Cbf5/dyskerin at a shared, structurally homologous surface, with Naf1 replaced by Gar1 during maturation.