What is the Difference Between Nuclear Lamina and Nuclear Matrix

The key difference between nuclear lamina and nuclear matrix is that nuclear lamina is a dense fibrillar network associated with the inner surface of the inner nuclear membrane of the nuclear while nuclear matrix is a fibrillar network found throughout inside the nucleus of a eukaryotic cell.

The nucleus is a membrane-bound structure that contains hereditary information. It usually controls the growth and reproduction of the cell. It is the most prominent organelle in eukaryotic cells and accounts for 10% of the total volume of the cell. The structure of the nucleus encompasses nuclear membrane (envelope), nucleoplasm, chromosomes, nucleolus, and fibrillar networks. Nuclear lamina and nuclear matrix are two different fibrillar networks found in the nucleus of eukaryotic cells.

CONTENTS

1. Overview and Key Difference
2. What is Nuclear Lamina
3. What is Nuclear Matrix
4. Similarities – Nuclear Lamina and Nuclear Matrix
5. Nuclear Lamina vs Nuclear Matrix in Tabular Form
6. Summary – Nuclear Lamina vs Nuclear Matrix

What is Nuclear Lamina?

Nuclear lamina is a dense fibrillar network associated with the inner surface of the inner nuclear membrane of a eukaryotic cell. Nuclear lamina is composed of intermediate filaments and membrane-associated proteins. Lamins are the type V intermediate filaments in nuclear lamina. Lamins can be categorized as type A (lamin A, C) or type B (lamin B1, B2) according to homology of their DNA sequences, biochemical properties, and cellular localization during cell cycle. Moreover, in vertebrate genome, there are three genes that are encoded for lamins. The nuclear lamin-associated membrane proteins are either integral or peripheral type membrane proteins. The most important lamins associated proteins are polypeptides 1 and 2 (LAP1, LAP2), emerin, lamin B- receptor (LBR), otefin, and MAN1.

There are many functions performed by nuclear lamina: providing mechanical support and regulating important cellular events like DNA replication and cell division. In addition, it also participates in chromatin organization and helps the embedding of nuclear pore complexes in the nuclear envelope.

What is Nuclear Matrix?

Nuclear matrix is a fibrillar network found inside the nucleus of a eukaryotic cell. Nuclear matrix can be clearly identified after a specific method of chemical extraction. It contains the nuclear lamina, residual nucleoli, a granular and fibrous matrix structure extending throughout the nucleus, and ribonucleoproteins. Nuclear matrix is very similar to the cytoskeleton of the cell.

Moreover, along with the nuclear membrane, nuclear matrix aids in organizing genetic information within the cell. Furthermore, it is also responsible for maintaining the shape of the nucleus and the spatial organization of chromatin. It also participates in several cellular processes, including DNA replication, repair, gene expression, RNA transport, cell signalling, cell differentiation, cell cycle regulation, apoptosis, and carcinogenesis.

What are the Similarities Between Nuclear Lamina and Nuclear Matrix?

• Nuclear lamina and nuclear matrix are two different fibrillar networks in the nucleus of a eukaryotic cell.
• Both fibrillar networks have intermediate filaments.
• They consist of specific proteins.
• They play a vital role in eukaryotic cells in maintaining the shape of the nucleus and other cellular processes.

What is the Difference Between Nuclear Lamina and Nuclear Matrix?

Nuclear lamina is a dense fibrillar network associated with the inner surface of the inner nuclear membrane of the nuclear envelope in the nucleus of a eukaryotic cell, while nuclear matrix is a fibrillar network found inside the nucleus of a eukaryotic cell. Thus, this is the key difference between nuclear lamina and nuclear matrix. Furthermore, nuclear lamina contains proteins such as polypeptides 1 and 2 (LAP1, LAP2), emerin, lamin B- receptor (LBR), otefin, and MAN1, but nuclear matrix contains proteins such as lamin associated proteins, structural proteins, chaperones, DNA/RNA binding proteins, chromatin remodelling proteins, and transcriptions factors.

The below infographic presents the differences between nuclear lamina and nuclear matrix in tabular form for side by side comparison.

Summary – Nuclear Lamina vs Nuclear Matrix

Nuclear lamina and nuclear matrix are networks of fibres found in the nucleus of eukaryotic cells. Nuclear lamina is a dense fibrillar network associated with the inner surface of the inner nuclear membrane, while nuclear matrix is a fibrillar network found inside the nucleus of a eukaryotic cell. So, this is the key difference between nuclear lamina and nuclear matrix.

Reference:

1. “Nuclear Matrix.” An Overview | ScienceDirect Topics.
2. “Nuclear Lamina.” An Overview | ScienceDirect Topics.

Image Courtesy:

1. “The three layers of NE proteins” By Ya-Hui Chi , Zi-Jie Chen and Kuan-Teh Jeang – The nuclear envelopathies and human diseases (CC BY 2.0) via Commons Wikimedia
2. “SMARs facultative” By Juergen Bode at the English Wikipedia (CC BY-SA 3.0) via Commons Wikimedia