- 関
- synapsis
WordNet
- the side by side pairing of homologous maternal and paternal chromosomes at the start of meiosis
- a threadlike strand of DNA in the cell nucleus that carries the genes in a linear order; "humans have 22 chromosome pairs plus two sex chromosomes"
- the act of grouping things or people in pairs
PrepTutorEJDIC
- 染色体
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出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2014/07/28 18:17:55」(JST)
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A bivalent, sometimes referred to as a tetrad, is a pair of associated homologous chromosomes held together by a complex after chromosome replication. During meiosis (the Prophase I: Pachynema stage of Meiosis I), the process of synapsis occurs in which bivalents are formed. Each replicated chromosome is composed of two chromatids.
Bivalents are formed as two homologous chromosomes undergo recombination. Chromosome movement to accommodate recombination places homologous chromosomes close enough to each other for a protein complex (synaptonemal complex), consisting of a protein (ZIP1/ZYP1 depending on species), to hold them together. This protein's sequence is not well conserved, though its structure is very similar in all species (globular domains on the N and C termini with a well defined core). A tetrad is made up of four chromatids or two pairs of sister chromatids.
In the atypical model species D. melanogaster and C. elegans recombination occurs secondarily to synapsis.
Recombination produces chiasmata which hold chromosomes together after the synaptonemal complex dissolves. (Prophase 1 substage Diplotene)
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English Journal
- Initiation of Meiotic Development Is Controlled by Three Posttranscriptional Pathways in Caenorhabditis elegans.
- Mohammad A1, Vanden Broek K2, Wang C2, Daryabeigi A3, Jantsch V3, Hansen D2, Schedl T4.
- Genetics.Genetics.2018 Jun 25. pii: genetics.300985.2018. doi: 10.1534/genetics.118.300985. [Epub ahead of print]
- PMID 29941619
- The Ubx Polycomb response element bypasses an unpaired Fab-8 insulator via cis transvection in Drosophila.
- Lu D1,2,3, Li Z1, Li L4, Yang L1, Chen G1, Yang D1, Zhang Y1, Singh V5, Smith S5, Xiao Y1, Wang E1,2, Ye Y1,2, Zhang W1,2, Zhou L6, Rong Y4, Zhou J1.
- PloS one.PLoS One.2018 Jun 21;13(6):e0199353. doi: 10.1371/journal.pone.0199353. eCollection 2018.
- PMID 29928011
- ARKS: chromosome-scale scaffolding of human genome drafts with linked read kmers.
- Coombe L1, Zhang J1, Vandervalk BP1, Chu J1, Jackman SD1, Birol I1, Warren RL2.
- BMC bioinformatics.BMC Bioinformatics.2018 Jun 20;19(1):234. doi: 10.1186/s12859-018-2243-x.
- PMID 29925315
Japanese Journal
- Characterization of Synthetic Hexaploids Derived from Same Aegilops tauschii Accessions and Different Durum Cultivars
- Cytomorphological and Molecular Characterization of F1 Hybrids between Brassica tournefortii and B. rapa
- Protein phosphatase 4 promotes chromosome pairing and synapsis, and contributes to maintaining crossover competence with increasing age.
Related Links
- This compact form makes the individual chromosomes visible, and they form the classic four arm structure, a pair of sister chromatids attached to each other at the centromere. The shorter arms are called p arms (from the French petit, small) ...
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★リンクテーブル★
[★]
- 英
- chromosome pairing
- 関
- 対合
[★]
- 関
- association、synapsis