6j07
From Proteopedia
Crystal structure of human TERB2 and TERB1
Structural highlights
Function[TERB2_HUMAN] Meiosis-specific telomere-associated protein involved in meiotic telomere attachment to the nucleus inner membrane, a crucial step for homologous pairing and synapsis. Component of the MAJIN-TERB1-TERB2 complex, which promotes telomere cap exchange by mediating attachment of telomeric DNA to the inner nuclear membrane and replacement of the protective cap of telomeric chromosomes: in early meiosis, the MAJIN-TERB1-TERB2 complex associates with telomeric DNA and the shelterin/telosome complex. During prophase, the complex matures and promotes release of the shelterin/telosome complex from telomeric DNA.[UniProtKB:Q9D494] [TERB1_HUMAN] Meiosis-specific telomere-associated protein involved in meiotic telomere attachment to the nucleus inner membrane, a crucial step for homologous pairing and synapsis. Component of the MAJIN-TERB1-TERB2 complex, which promotes telomere cap exchange by mediating attachment of telomeric DNA to the inner nuclear membrane and replacement of the protective cap of telomeric chromosomes: in early meiosis, the MAJIN-TERB1-TERB2 complex associates with telomeric DNA and the shelterin/telosome complex. During prophase, the complex matures and promotes release of the shelterin/telosome complex from telomeric DNA. In the MAJIN-TERB1-TERB2 complex, TERB1 probably mediates association with the shelterin/telosome complex via interaction with TERF1, promoting priming telomeric DNA attachment'. Promotes telomere association with the nuclear envelope and deposition of the SUN-KASH/LINC complex. Also recruits cohesin to telomeres to develop structural rigidity.[UniProtKB:Q8C0V1] Publication Abstract from PubMedDuring meiotic prophase I, telomeres attach to and move on the nuclear envelope (NE), regulating chromosome movement to promote homologous pairing. Meiosis-specific proteins TERB1, TERB2 and MAJIN play a key role in this process. Here, we report the crystal structures of human TERB1-TERB2 and TERB2-MAJIN subcomplexes. Specific disruption of the TERB1-TERB2 or the TERB2-MAJIN interaction in the mouse Terb2 gene abolishes the telomere attachment to the NE and causes aberrant homologous pairing and disordered synapsis. In addition, depletion of SUN1 also partially disrupts the telomere-NE connection. We propose that the telomere-TRF1-TERB1-TERB2-MAJIN-NE interaction network and the telomere-LINC complex connection are likely two separate but cooperative pathways to stably recruit telomeres to the NE in meiosis prophase I. Our work provides a molecular model of the connection between telomeres and the NE and reveals the correlation between aberrant synapsis and the defective telomere attachment to the NE. The meiotic TERB1-TERB2-MAJIN complex tethers telomeres to the nuclear envelope.,Wang Y, Chen Y, Chen J, Wang L, Nie L, Long J, Chang H, Wu J, Huang C, Lei M Nat Commun. 2019 Feb 4;10(1):564. doi: 10.1038/s41467-019-08437-1. PMID:30718482[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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