Drawing of the anchorage of the LINC complex

Figure 3. Anchoring the LINC complex. Mammalian SUN proteins are anchored to the inner nuclear membrane through at least three different mechanisms. (A) The nucleoplasmic tail of SUN2 binds to lamin A and anchors the LINC complex to the nuclear lamina in somatic cells. Samp1 and emerin are required to strengthen this anchorage during nuclear movement, presumably to resist the high mechanical force. For clarity, nesprin-2G is shown as a shorter protein without all of its 56 SRs. INM, inner nuclear membrane; ONM, outer nuclear membrane. (B) The nucleoplasmic tail of SUN1 binds TERB1 and anchors the LINC complex to chromosomes through telomere binding proteins (TRF1 and cohesion) in meiotic cells. Lamin C2 also associates with this complex, probably through SUN1 binding. (C) Nucleoplasmic tails of SUN proteins shown binding to nuclear pores (SUN1) and a hypothetical protein as possible alternative anchors for the LINC complex in somatic cells. As described in the text, the localization of SUN1 and SUN2 in the nuclear membrane is only slightly affected in somatic cells lacking all lamins, which indicates the presence of additional anchoring factors.

Anchoring the LINC complex, with lables (2500 × 1200 px).

Anchoring the LINC complex, without lables (2500 × 1200 px).