粘着蛋白和冷凝蛋白之间的差异

Thekey differencebetween cohesin and condensin is thatcohesin is a tetrameric protein complex which holds姐妹染色质酸紧紧地在一起虽然condensin pentameric protein complex required for chromosome condensation.

Cohesin and condensin are two multi-component proteins that are important in sister chromatid segregation incell division. Cohesin is essential during the中期, while condensin is essential during theanaphase. When going from metaphase to anaphase, condensin replaces cohesin and allows sister chromatids to reach their respective poles. Structurally and functionally, these two proteins differ from each other.

内容

1.Overview and Key Difference
2.What is Cohesin
3.What is Condensin
4.Similarities Between Cohesin and Condensin
5.Side by Side Comparison – Cohesin vs Condensin in Tabular Form
6。概括

什么是粘蛋白？

Cohesin is a protein that holds sister chromatids together after DNA replication until anaphase occurs, and it is the right time to separate sister chromatids from each other. Structurally, cohesin is a multi-subunit protein complex which actually has four core subunits. Out of the four subunits, two are SMC proteins (SMC1 (structural maintenance of chromosome protein 1) and SMC3 (structural maintenance of chromosome protein 3), which have two main structural domains as head and hinge domains. Other two subunits are two long coiled-coil molecules. Due to cohesin protein, sister chromatids segregate to two poles correctly. Otherwise, cells cannot control the segregation of sister chromatids into each pole during the anaphase.

Cohesin also facilitates the attachment of spindle fibres to chromosomes. In addition, cohesin mediates DNA repairing by recombination.

What is Condensin?

Condensin is a pentameric protein complex needed for chromosome condensation. It consists of five subunits, including two SMC proteins and three auxiliary subunits. SMC proteins in condensing are SMC2 and SMC4. Condensin fulfils several functions in genome regulation, including mitotic and meiotic division, DNA repair, transcriptional control, and chromosome condensation.

There are two types of condensins as condensin I and condensin II. Condensin I regulates the timing of chromosome condensation while condensin II facilitates the compaction of the chromosome loops along the sister chromatid axes.

What are the Similarities Between Cohesin and Condensin?

• Cohesin and condensin are proteins that act as molecular cross-linkers.
• 凝聚力和冷凝蛋白都在染色体分离中有用。
• They are also essential for mitotic chromosome architecture, the regulation of sister chromatid pairing, DNA repair and replication, and the regulation of gene expression.
• They are close functional and structural relatives.
• Both are multi-component molecules.
• SMC蛋白是内聚和冷凝蛋白的成分。
• They are ring-like molecules.

What is the Difference Between Cohesin and Condensin?

Cohesin holds replicated sister chromatids together until they separate at anaphase while condensin reorganizes chromosomes into their highly compact mitotic structure. So, this is the key difference between cohesin and condensin. Furthermore, cohesin is a tetramer composed of four subunits, while condensing is a pentameric protein composed of five subunits.

The below infographic summarizes the difference between cohesin and condensin.

概括– Cohesin vs Condensin

粘着蛋白和冷凝蛋白是结构和功能亲戚，它们是多组分蛋白。它们对于在细胞分裂期间将基因组的相同副本分离为子细胞至关重要。两者都包含SMC蛋白，它们是环状结构。然而，粘着蛋白是四聚蛋白，而冷凝蛋白是一种五聚体蛋白。此外，粘着蛋白含有SMC1和SMC3，而冷凝蛋白含有SMC2和SMC4。因此，这总结了粘着蛋白和冷凝蛋白之间的差异。

Reference:

1. Makrantoni, Vasso, and Adele L Marston. “Cohesin and Chromosome Segregation.” Current Biology: CB, Cell Press, 18 June 2018,Available here.
2. “Condensin.” Condensin – an Overview | ScienceDirect Topics,Available here.

Image Courtesy:

1.英语Wikipedia的BlastWizard的“粘蛋白” - 从En.Wikipedia转移到Commons，由Vojtech.dostal。(CC BY-SA 3.0)viaCommons Wikimedia
2. “3condensins2(en)” By Ascendinglotus2 – Own work(CC BY-SA 3.0)viaCommons Wikimedia