meiotic telomere clustering
Definition
Target type: biologicalprocess
The cell cycle process in which the dynamic reorganization of telomeres occurs in early meiotic prophase, during which meiotic chromosome ends are gathered in a bouquet arrangement at the inner surface of the nuclear envelope proximal to the spindle pole body. This plays an important role in progression through meiosis and precedes synapsis. [GOC:vw, PMID:10690419]
Meiotic telomere clustering is a crucial process that occurs during the prophase I stage of meiosis, specifically during the zygotene and pachytene substages. This process ensures proper homologous chromosome pairing and synapsis, which is essential for accurate segregation of chromosomes during meiosis I.
During zygotene, telomeres, the specialized structures at the ends of chromosomes, begin to associate with the nuclear envelope. This association is mediated by specific proteins, including the telomere-binding protein TRF2 and the nuclear envelope protein SUN1. As chromosomes continue to condense, telomeres from different chromosomes move closer together, ultimately forming a cluster at the nuclear periphery. This clustering is facilitated by the formation of a specialized structure called the telomere bouquet.
The telomere bouquet is a dynamic structure that constantly rearranges, allowing telomeres to explore the nuclear space and search for their homologous counterparts. As the telomere bouquet forms, chromosomes become progressively more organized, with sister chromatids tightly associated. This organization allows for the precise pairing of homologous chromosomes, which is a prerequisite for synapsis.
Synapsis is the process by which homologous chromosomes align along their entire length, forming a structure called the synaptonemal complex (SC). The SC is a proteinaceous structure that serves as a scaffold for the precise pairing and recombination of homologous chromosomes. Telomere clustering is essential for the efficient formation of the SC. It ensures that all telomeres are brought into close proximity, increasing the likelihood that homologous chromosomes will encounter each other and initiate synapsis.
Once synapsis is complete, telomere clustering gradually dissipates. This suggests that telomere clustering is a transient process that is specifically required for the initial stages of meiotic chromosome pairing and synapsis. Disruption of telomere clustering can lead to improper chromosome pairing, which can result in aneuploidy (an abnormal number of chromosomes) and other meiotic defects.
In summary, meiotic telomere clustering is a tightly regulated process that involves the coordinated action of multiple proteins. It plays a crucial role in the accurate pairing and synapsis of homologous chromosomes during prophase I of meiosis. Proper telomere clustering is essential for ensuring the faithful segregation of chromosomes during meiosis I, contributing to the genetic stability of offspring.'
"
Proteins (1)
| Protein | Definition | Taxonomy |
|---|---|---|
| Serine-protein kinase ATM | A serine-protein kinase ATM that is encoded in the genome of human. [PRO:CNA] | Homo sapiens (human) |
Compounds (20)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| pd 173074 | aromatic amine; biaryl; dimethoxybenzene; pyridopyrimidine; tertiary amino compound; ureas | antineoplastic agent; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor; fibroblast growth factor receptor antagonist | |
| caffeine | purine alkaloid; trimethylxanthine | adenosine A2A receptor antagonist; adenosine receptor antagonist; adjuvant; central nervous system stimulant; diuretic; EC 2.7.11.1 (non-specific serine/threonine protein kinase) inhibitor; EC 3.1.4.* (phosphoric diester hydrolase) inhibitor; environmental contaminant; food additive; fungal metabolite; geroprotector; human blood serum metabolite; mouse metabolite; mutagen; plant metabolite; psychotropic drug; ryanodine receptor agonist; xenobiotic | |
| 2-(4-morpholinyl)-8-phenyl-4h-1-benzopyran-4-one | 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one: specific inhibitor of phosphatidylinositol 3-kinase; structure in first source | chromones; morpholines; organochlorine compound | autophagy inhibitor; EC 2.7.1.137 (phosphatidylinositol 3-kinase) inhibitor; geroprotector |
| schizandrin b | schizandrin B: a phytogenic antineoplastic agent with anti-inflammatory activity; isolated from Schisandra plant | ||
| thiourea | thiourea : The simplest member of the thiourea class, consisting of urea with the oxygen atom substituted by sulfur. Thiourea: A photographic fixative used also in the manufacture of resins. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), this substance may reasonably be anticipated to be a carcinogen (Merck Index, 9th ed). Many of its derivatives are ANTITHYROID AGENTS and/or FREE RADICAL SCAVENGERS. | one-carbon compound; thioureas; ureas | antioxidant; chromophore |
| ku 55933 | 2-morpholin-4-yl-6-thianthren-1-yl-pyran-4-one: specific inhibitor of the ataxia-telangiectasia mutated kinase ATM; structure in first source | ||
| cgk 733 | diarylmethane | ||
| nu 7026 | 2-(morpholin-4-yl)benzo(h)chromen-4-one: a radiosensitizing agent that inhibits DNA-dependent protein kinase; structure in first source | organic heterotricyclic compound; organooxygen compound | |
| nu 7441 | 8-dibenzothiophen-4-yl-2-morpholin-4-yl-chromen-4-one: structure in first source | dibenzothiophenes | |
| ku-0060648 | dibenzothiophenes | ||
| dactolisib | dactolisib : An imidazoquinoline that is 3-methyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-c]quinoline substituted at position 1 by a 4-(1-cyanoisopropyl)phenyl group and at position 8 by a quinolin-3-yl group. A dual PI3K/mTOR inhibitor used in cancer treatment. dactolisib: antineoplastic agent that inhibits both phosphatidylinositol 3-kinase and mTOR | imidazoquinoline; nitrile; quinolines; ring assembly; ureas | antineoplastic agent; EC 2.7.1.137 (phosphatidylinositol 3-kinase) inhibitor; mTOR inhibitor |
| ku 60019 | |||
| cp 466722 | quinazolines | ||
| (3R)-4-[2-(1H-indol-4-yl)-6-(1-methylsulfonylcyclopropyl)-4-pyrimidinyl]-3-methylmorpholine | indoles | ||
| ve 821 | 3-amino-6-(4-(methylsulfonyl)phenyl)-N-phenylpyrazine-2-carboxamide: an antineoplastic agent; structure in first source | aromatic amide | |
| torin 2 | torin 2 : A member of the class of pyridoquinolines that is benzo[h][1,6]naphthyridin-2-one carrying additional 3-(trifluoromethyl)phenyl and 6-aminopyridin-3-yl substituents at positions 1 and 9 respectively. It is a potent inhibitor of mTOR and exhibits anti-cancer properties. | aminopyridine; organofluorine compound; primary amino compound; pyridoquinoline | antineoplastic agent; mTOR inhibitor |
| byl719 | proline derivative | ||
| cc-115 | 1-ethyl-7-(2-methyl-6-(1H-1,2,4-triazol-3-yl)pyridin-3-yl)-3,4-dihydropyrazino(2,3-b)pyrazin-2(1H)-one: an mTOR kinase inhibitor; structure in first source | ||
| vx-970 | berzosertib: an ATR kinase inhibitor | sulfonamide | |
| etp-46464 | ETP-46464: inhibits ATM and Rad3-related kinase; structure in first source |