Difference Between Centromere and Kinetochore

Thekey difference在Centromere和Kinetochore之间是centromere is the region of the染色体持有两个姐妹染色质酸在复制染色体后一起，而动力学是染色体的圆盘形蛋白质复合物，使纺锤纤维在固定过程中连接cell division.

遗传信息的遗传取决于有丝分裂和减数分裂过程中染色体的正确分离。有丝分裂是遗传上相同的子细胞的产生，而减数分裂是子细胞的产生，该子细胞包含一对父母细胞中存在的每对染色体。此外，染色体分离是一个极为准确的过程。它的微结构和形状对于隔离过程非常重要。同样，此过程完全取决于microtubules. The sites of attachment of microtubules, therefore, should have certain specific properties. Centromere and kinetochore are two regions of the chromosomes that play a major role during the cell division. The main aim of this article is to highlight the difference between centromere and kinetochore.

内容

1.Overview and Key Difference
2.What is Centromere
3.什么是动力学
4.Centromere和Kinetochore之间的相似之处
5.Side by Side Comparison – Centromere vs Kinetochore in Tabular Form
6。概括

什么是Centromere？

A centromere is a highly constricted region on a chromosome that holds two sister chromatids together in a chromosome. It also allows spindle fibers to attach to it during the process of mitosis and meiosis. These special regions contain non-histone proteins that protect them from endonuclease digestion and they are free of nucleosomes. The major role of the centromere is to provide sites for kinetochores.

In eukaryotes, the sizes of the centromeres vary, but all have the same function. Most eukaryotes have monocentric centromeres, where the centromere-kinetochore complex forms at a single point on the chromosome except in some nematodes. Unlike in unicellular organisms, centromeres of multicellular organisms exist embedded within the constructive centricheterochromatin. Centromere has highly specialized repetitive DNA sequences. Furthermore, it only binds with a unique set of proteins. These regions, therefore, chemically differ from the rest of the chromosome.

什么是动力学？

动力学is a disc-shaped protein complex present in the centromere region of a chromosome which is in the mitotic or meiotic division. Each chromosome has a kinetochore. The functions of these complexes are to bind microtubules of the spindle bundle and depolarize them during the cell division. Many animal cells contain disc-like kinetochores with three distinct layers that form on one side of each chromatid. The inner layer of the kinetochore is associated with the centromere while the outer layer interacts with microtubules. The function of the middle layer is unknown. The number of bound microtubules to a kinetochore varies with the species. For example, human kinetochore binds approximately with 15 microtubules whereas kinetochore of Saccharomyces binds with only one microtubule.

In certain organisms like protozoa, some fungi, and insects, kinetochores cannot be visualized as proteins disintegrate during preparation. Unattached kinetochores have extending-fibers that contain many proteins known as corona. These coronas help to capture microtubules during the cell division. The microtubules associated with kinetochores have long lives, while those in the rest of the spindle have very short lives.

Centromere和Kinetochore之间有什么相似之处？

• Both centromere and kinetochore are present in the chromosomes.
• They are extremely important for cell division.
• And, they are visualized during the cell division.

What is the Difference Between Centromere and Kinetochore?

Centromere是在具有高度专业的重复DNA序列的染色体上发现的狭窄区域。鉴于，动力学是在染色体的丝粒区域发现的圆盘形蛋白质复合物。因此，这是Centromere和Kinetochore之间的关键区别。此外，Centromere和Kinetochore之间的显着差异是，在光学显微镜下清楚地看到了丝粒作为凝结染色体上的狭窄区域，而只能借助电学显微镜看到动力学。此外，与中心粒不同，动元有三个不同的层。因此，这也是Centromere和Kinetochore之间的差异。

Moreover, a further difference between centromere and kinetochore is that the kinetochore has corona while no such structures are found in centromeres. Besides, the centromeres cannot bind with the microtubules. Only the kinetochores that are associated with centromeres have the ability to bind microtubules. Therefore, we can consider this also as a difference between centromere and kinetochore.

Below infographic summarizes the difference between centromere and kinetochore.

概括– Centromere vs Kinetochore

丝粒是染色体中的收缩点。它在组蛋白周围具有高度冷凝的染色质。它将两个染色体的姐妹染色单体扎在一起。另一方面，Kinetochore是一种蛋白质复合物，该蛋白质复合物围绕染色体的丝粒组装。它提供了在细胞分裂期间附着微管的位点。Centromere和Kinetochore均确保细胞分裂期间染色体和染色单体的正确分裂和分离。因此，这是Centromere和Kinetochore之间差异的摘要。

Reference:

1. “Kinetochore.” Wikipedia, Wikimedia Foundation, 22 Feb. 2019,Available here.
2. “Centromere – Definition and Structure.” Study.com,Available here.

Image Courtesy:

1. “Figure 10 02 03” ByCNX OpenStax–（CC由4.0）viaCommons Wikimedia
2. Dawn08的“染色体凝聚力 - EN” - 自己的作品(CC BY-SA 3.0)viaCommons Wikimedia