Cellular and Molecular Biology

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Nuclear Lamina: Origin and Function in Gene Control

CELLS-EU1GZ4

The nuclear lamina is a fibrous structure located on the internal surface of the nuclear envelope of only multicellular eukaryotes. It is composed of several forms of the intermediate protein filament, laminin, and laminin-associated proteins.

One of its functions is to tether chromatin to the nuclear envelope thereby organizing chromatin and controlling gene expression. Heterochromatin, chromatin that is infrequently used, is preferentially located near the nuclear periphery.

The nuclear lamina also acts to support nuclear shape. Mutations in genes responsible for the formation of this lamina cause abnormally shaped nuclei and pathologies such as Hutchinson-Gilford progeria syndrome. This syndrome is characterized by greatly accelerated aging.

Celeste R. Wirsig-Wiechmann Created for Albert.io. Copyright 2016. All rights reserved.

From the passage above and/or from what you know about cell biology, which of the following statements is TRUE?

A

The nuclear lamina is composed of tubulin.

B

The components of the nuclear lamina are synthesized in the cytoplasm of the cell.

C

Normal aging is caused by degeneration of the nuclear lamina.

D

The nuclear lamina is found in all eukaryotic cells.

E

Euchromatin is preferentially located on the peripheral surface of the nuclear envelope.