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The lamin protein family
Travis A Dittmer1, Tom Misteli
1National Cancer Institute, National Institutes of Health, Bethesda, MD 20896, USA. dittmert@mail.nih.gov
Genome Biology
|June 7, 2011
Summary
Lamins are crucial nuclear architectural proteins providing structural support and regulating genome functions. Mutations in these intermediate filaments cause laminopathies, highlighting their vital role in cell health.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Lamins are the primary structural proteins within the animal cell nucleus.
- They form a meshwork lining the nuclear membrane, essential for mechanical stability and organizing chromatin.
- Lamins are the sole nuclear members of the intermediate filament (IF) protein family.
Purpose of the Study:
- To summarize the structural and functional significance of lamins in nuclear architecture.
- To highlight the role of lamins in various nuclear processes like genome organization and DNA repair.
- To underscore the importance of lamins by discussing diseases caused by their mutations.
Main Methods:
- Review of existing literature on lamin structure and function.
- Analysis of the tripartite protein structure common to intermediate filaments.
- Examination of the pathological consequences of lamin gene mutations.
Main Results:
- Lamins polymerize into fibers, forming a complex nuclear meshwork.
- They play critical roles in higher-order genome organization, chromatin regulation, transcription, DNA replication, and repair.
- Mutations in lamins lead to a spectrum of human diseases known as laminopathies.
Conclusions:
- Lamins are indispensable nuclear architectural proteins with diverse cellular functions.
- Their structural role and involvement in fundamental nuclear processes are critical for cell viability.
- Understanding laminopathies emphasizes the essential contribution of lamins to human health.
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