Fig. 3
From: Structural basis of meiotic telomere attachment to the nuclear envelope by MAJIN-TERB2-TERB1
Solution structure of MAJIN–TERB2. a SEC-MALS analysis; light scattering (LS) and differential refractive index (dRI) profiles are overlaid, with fitted molecular weights (Mw) plotted as diamonds across elution peaks. Wild type (black, left) and truncated (grey, left) MAJINCore-TERB2C complexes (WT: 1–112, 168–220; Tr: 1–106, 168–207) form 2:2 hetero-tetramers of 43 kDa and 35 kDa, respectively (theoretical 2:2–40 kDa and 35 kDa). MAJIN mutations F73E Y75E (black, right), and K24M K26E R28E K31D R34E R81D (basic surface mutant; grey, right) block dimerization of MAJINCore-TERB2C, leaving 1:1 complexes of 21 kDa and 20 kDa, respectively (theoretical 1:1–20 kDa). b–e SEC-SAXS analysis. b SAXS scattering curves of MAJINCore-Tr–TERB2C-Tr and MAJINΔTM–TERB2C-Tr (1–233, 168–207) overlaid with theoretical scattering curves of the crystal structure (red; χ2 = 1.62 and 93.0, respectively) and a CORAL model of the crystal structure with modelled MAJIN C-termini (blue; χ2 = 1.24 for MAJINΔTM-TERB2C-Tr). The scattering data points below the minimum Q-value of the Guinier analysis are shown in grey. c SAXS P(r) distributions of MAJINCore-Tr-TERB2C-Tr (black, solid), MAJINCore–TERB2C (black, dashed) and MAJINΔTM–TERB2C-Tr (grey), showing maximum dimensions of 80 Å, 120 Å and 155 Å, respectively. Their real space Rg values of 24 Å, 32 Å and 39 Å closely match their Guinier Rg values of 24 Å, 30 Å and 37 Å (Supplementary Fig. 4a–c), respectively. d SAXS ab initio model of MAJINCore-Tr–TERB2C-Tr. A filtered averaged model was generated from 30 independent DAMMIF runs, imposing P2 symmetry, with NSD = 0.904 (± 0.115) and reference model χ2 = 1.59, and is displayed as a molecular envelope with the docked crystal structure. e SAXS CORAL model of MAJINΔTM–TERB2C-Tr in which MAJIN C-termini were modelled onto the MAJINCore-TERB2C crystal structure up to residue 233 through fitting to experimental SAXS data (χ2 = 1.24). The model is displayed with a cartoon of C-terminal transmembrane helices inserted in the inner nuclear membrane (INM), highlighting how unstretched MAJIN C-terminal linkers may provide a separation of approximately 90 Å between the nuclear envelope and MAJIN–TERB2 core
