Synaptonemal complex

Definition
noun, plural: synaptonemal complexes
A complex protein structure that spans the region between the paired homologous chromosomes in prophase I of meiosis I
Supplement
Meiosis is form of cell division that gives rise to genetically diverse sex cells or gametes. It is comprised to two successive nuclear divisions namely meiosis I and meiosis II. Meiosis I is comprised of four stages: prophase I, metaphase I, anaphase I, and telophase I. Prophase I is the first stage and consists of the following sub-stages: leptotene, zygotene, pachytene, diplotene and diakinesis.
The synaptonemal complex is a zipper-like proteinaceous structure that is formed during prophase I of meiosis I. It is evident particularly during the zygotene stage. Prior to zygotene, the chromosomes begin to condense and at this stage the chromomeres become more discernible as beadlike structures along the chromosome. These chromomeres aid in the pairing of homologous chromosomes. The complete pairing or coming together of homologous chromosomes (called synapsis) takes place in zygotene. Synapsis may be facilitated by the synaptonemal complex. The complex aids in the stabilization of the pairing of homologous chromosomes and promotes the formation of chromosomal crossovers.¹
Abbreviation / Acronym: SC
Variant:

• synaptinemal complex

See also:

Reference(s):

¹ Heyting, C. (1996). Synaptonemal complexes: structure and function. Curr Opin Cell Biol. 8(3):389-96.