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06:56
Generating a Fractal Microstructure of Laminin-111 to Signal to Cells
Published on: September 28, 2020
Filaments made from A- and B-type lamins differ in structure and organization
Martin W Goldberg1, Irm Huttenlauch, Christopher J Hutchison
1School of Biological and Biomedical Sciences, The University of Durham, South Road, Durham DH1 3LE, UK. m.w.golberg@durham.ac.uk
Journal of Cell Science
|January 12, 2008
Summary
Nuclear lamina organization is reinterpreted as interconnected parallel filaments, not perpendicular arrays. Exogenous somatic lamins (A and B) assemble into filaments in oocytes, revealing new insights into nuclear envelope structure and rigidity.
Area of Science:
- Cell Biology
- Structural Biology
- Biochemistry
Background:
- Lamins are key intermediate filament proteins forming the nuclear lamina.
- Current understanding of the nuclear lamina is based on amphibian oocyte lamin LIII organization.
- In situ studies of somatic lamins are challenging due to chromatin association and in vitro assembly difficulties.
Purpose of the Study:
- To re-examine the organization of the amphibian oocyte lamin LIII.
- To propose a new model for nuclear lamina structure.
- To investigate the in vivo assembly and organization of exogenous somatic lamins (A and B types) using the oocyte system.
Main Methods:
- Re-examination of amphibian oocyte lamin LIII organization.
- Expression of exogenous somatic B-type and A-type lamins in oocytes.
- Analysis of filament assembly and nuclear envelope properties following exogenous lamin expression.
Main Results:
- The oocyte lamina is proposed to consist of interconnected parallel filaments, not perpendicular arrays.
- Exogenous somatic B-type lamins assemble into filaments, inducing intranuclear membranes.
- Exogenous somatic A-type lamins form thicker filaments, increasing nuclear envelope rigidity.
Conclusions:
- A revised model for nuclear lamina organization based on interconnected parallel filaments is proposed.
- The oocyte system is effective for studying somatic lamin assembly and function in vivo.
- Somatic lamins A and B play distinct roles in nuclear envelope structure and mechanical properties.
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