Lamin
The type V intermediate filaments are called lamines .
The lamines can be found in the nucleus of eukaryotic cells , where they are anchored to the inner nuclear membrane via a large number of membrane-bound proteins (e.g. Emerin ) . As usual for intermediate filaments, the lamines also have a three-part domain structure . A relatively short head area merges into the conserved rod domain. It consists of 4 coiled coil sections that are connected to one another by variable linkers. The coiled coils have a characteristic heptad pattern in which hydrophobic amino acid residues are in the 1st and 4th position of a seven amino acid segment. The coiled-coil structure is formed via these hydrophobic amino acids. Two alpha-helical protein strands wind around each other. In contrast to the cytoplasmic IF proteins of the chordata , the coil 1b domain of lamines is 42 amino acids longer, a feature that can be found in all, including the cytoplasmic intermediate filaments of the protostomies (insects, nematodes, etc.). The tail domain follows at the end of the rod domain. It contains a nuclear localization signal , the 105 box (length 105 amino acids) and the carboxy-terminal CaaX box . It is highly conserved , with “C” standing for cysteine , “aa” for two aliphatic amino acids and “X” for any amino acid.
The interaction partners of the lamines include the proteins LAP2alpha , Rb ( retinoblastoma protein), and BAF (barrier-to-autointegration factor).
Individual evidence
- ↑ Dorner D, Gotzmann J, Foisner R: Nucleoplasmic lamins and their interaction partners, LAP2alpha, Rb, and BAF, in transcriptional regulation . In: FEBS J . . 274, No. 6, March 2007, pp. 1362-73. doi : 10.1111 / j.1742-4658.2007.05695.x . PMID 17489094 .