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Incoming links: Laminin
Lamin 2026-11-05
A lamin is a type of intermediate filament protein forming part of the nuclear lamina, a network associated with the inner surface of the nuclear envelope. Lamins contribute to nuclear shape and mechanical organization and interact with components connecting the envelope to chromatin. They differ from laminin, an extracellular-matrix protein, despite the similar names. [ref]
Molecular Biology of the Cell, 4th edition by Bruce Alberts and others. Chapter 12, The Nuclear Envelope: the nuclear lamina; Chapter 16, intermediate filaments
Regulated assembly is useful during cell division. Phosphorylation of lamins helps promote lamina disassembly as the nuclear envelope breaks down in open mitosis; subsequent reassembly supports daughter nuclei. Thus a structural protein can form a load-bearing network while retaining a chemically regulated route for dismantling it.
Laminin 2026-11-05
A laminin is a large extracellular glycoprotein of the basement membrane, the specialized extracellular matrix underlying many epithelial sheets and surrounding some individual cells. A laminin molecule contains three different polypeptide chains, conventionally called alpha, beta and gamma, assembled into an extended cross-like or related shape. Different chain combinations produce distinct laminins.[ref]
Molecular Biology of the Cell, 4th edition by Bruce Alberts and others. Chapter 19, Basal Laminae Are Composed Mainly of Type IV Collagen, Laminin, Nidogen, and a Heparan Sulfate Proteoglycan
Laminin links matrix organization to cellular behaviour: binding to cell adhesion receptors such as integrins helps a cell attach to its surroundings and orient its surfaces. Its location was established experimentally, not inferred from the name. In 1979, R. Timpl and colleagues isolated laminin from a mouse tumour producing abundant basement membrane material, then used antibodies to localize the isolated component in basement membranes.[ref]
Laminin--a glycoprotein from basement membranes by R. Timpl and others. Abstract and pp. 9933–9937
R. Timpl 2026-11-05
R. Timpl coauthored the 1979 isolation and characterization of laminin, a large glycoprotein associated with basement membranes. The researchers isolated it from a mouse tumour producing abundant basement-membrane material and used antibodies to investigate its distribution.[ref]
Laminin--a glycoprotein from basement membranes by R. Timpl and others. Abstract and pp. 9933–9937: isolation, biochemical characterization and immunological localization
Purification and localization answer complementary questions. Purification establishes a distinguishable molecular component; localization connects that component with a tissue structure. Finding both laminin and type IV collagen in the material helped show that a basement membrane is an organized extracellular assembly, rather than a layer made of one interchangeable protein.