| 2017 |
LEM2 acts as a conserved nuclear site-specific adaptor that directly binds CHMP7 (via its C-terminal winged-helix domain) and recruits downstream ESCRT-III factors (CHMP7, CHMP2A, IST1/CHMP8) to the nuclear envelope during nuclear envelope closure. Genetic epistasis in fission yeast showed lem2 and cmp7 loss-of-function suppresses vps4-deletion nuclear morphology defects, placing them upstream in the same pathway. |
In vitro direct binding assay (C-terminal domain of LEM2 binds CHMP7), genetic epistasis (suppressor screen in S. pombe), immunofluorescence co-localization in human cells, RNAi knockdown with loss-of-ESCRT-recruitment phenotype |
Proceedings of the National Academy of Sciences of the United States of America |
High |
28242692
|
| 2020 |
LEM2 undergoes phase separation via its low-complexity domain (LCD), which contains a proline-arginine-rich sequence that binds microtubules and targets LEM2 condensation to spindle microtubules at the nascent nuclear envelope. The LEM motif binds BAF conferring chromatin affinity. The winged-helix domain of LEM2 activates CHMP7 to form co-oligomeric rings. Disruption of phase separation or CHMP7 activation prevented downstream ESCRT recruitment, impaired spindle disassembly, and caused nuclear integrity defects and DNA damage. |
Phase separation assays, in vitro microtubule binding, domain mutagenesis, cross-linking mass spectrometry (XL-MS), fluorescence microscopy in human cells, loss-of-function phenotypic readouts (DNA damage, spindle disassembly defects) |
Nature |
High |
32494070
|
| 2005 |
LEM2 is an inner nuclear membrane protein containing an N-terminal LEM motif, two transmembrane domains, and a C-terminal MSC domain. It binds lamin C tail in vitro. Targeting to the nuclear envelope requires A-type lamins and is mediated by the N-terminal and transmembrane domains. Overexpressed LEM2 recruits A-type lamins, emerin, MAN1, and BAF, while excluding lamin B and lamin B receptor. |
In vitro binding assay (lamin C tail), immunofluorescence of digitonin-treated cells, subcellular fractionation, overexpression/domain truncation analysis |
Journal of cell science |
High |
16339967
|
| 2009 |
NET25/LEM2 is required for myogenic differentiation of C2C12 myoblasts. RNAi depletion causes hyperactivation of ERK1/2 at the onset of differentiation; pharmacological ERK inhibition rescues myogenesis. Ectopic silencing-resistant NET25 rescues differentiation after emerin depletion, indicating overlapping functions, but does not rescue after MAN1 depletion. |
RNAi knockdown in C2C12 myoblasts, pharmacological rescue (MEK/ERK inhibitors), ectopic expression of silencing-resistant constructs, differentiation assays |
Molecular and cellular biology |
High |
19720741
|
| 2015 |
Lemd2 knockout mice die by E11.5. Knockdown of Lem2 in C2C12 myoblasts activates multiple MAP kinases (ERK1/2, JNK, p38) and AKT, indicating Lem2 regulates these signaling pathways. Heterozygous mice show delayed muscle regeneration after cardiotoxin injury. |
Conditional knockout mouse (homozygous lethal at E11.5), Western blot for activated kinases in knockout embryos and siRNA-treated myoblasts, cardiotoxin muscle regeneration assay |
PloS one |
High |
25790465
|
| 2016 |
In S. pombe, the LEM domain of Lem2 mediates centromere chromatin binding and perinuclear tethering, while the MSC domain is required for heterochromatin silencing at telomeres and is epistatic with the SHREC (Snf2/HDAC repressor) complex. Loss of Lem2 reduces SHREC association with heterochromatin and increases Epe1 (anti-silencing JmjC protein) binding; these are separable, domain-specific functions. |
Genetic epistasis (lem2 deletion + SHREC/Epe1 mutant combinations), ChIP, domain deletion/truncation analysis, gene silencing reporter assays in S. pombe |
Genes & development |
High |
26744419
|
| 2016 |
In S. pombe, Lem2 physically associates with Nur1 (another inner nuclear membrane protein), forming a Lem2-Nur1 complex essential for heterochromatin-mediated gene silencing at centromeres, telomeres, and rDNA. ChIP-seq shows Lem2 binds central core regions of centromeres. Recruitment of Lem2 and Nur1 to silent regions depends on H3K9 methyltransferase Clr4. The complex regulates the balance between SHREC histone deacetylase complex and anti-silencing protein Epe1. |
Co-immunoprecipitation, ChIP-seq, genetic deletion analysis, silencing reporter assays in S. pombe |
The Journal of biological chemistry |
High |
27451393
|
| 2020 |
LEM2 has a unique interactome compared to MAN1 and emerin; the LEM2-specific interactome contains nucleotide excision repair (NER) pathway proteins. LEM2-depleted cells (but not MAN1- or emerin-depleted cells) show impaired proliferation after UV-C irradiation and prolonged γH2AX accumulation, indicating a specific role for LEM2 in NER-mediated DNA damage repair at the nuclear periphery. |
BioID proximity biotinylation interactome, siRNA knockdown, UV-C irradiation assay, γH2AX immunofluorescence |
Cells |
Medium |
32085595
|
| 2020 |
In C. elegans oocytes, LEM-2 (the LEMD2 ortholog) acts as an NE adaptor for ESCRT-III; loss of NE adaptors (including LEM-2) exacerbates ER membrane invasion into NE holes and nuclear permeability defects caused by loss of the NE phosphatase CNEP-1/CTDNEP1, placing LEM-2/ESCRT-III in a pathway that restricts excess ER membranes during NE closure. |
Genetic epistasis (double mutant analysis), 3D electron microscopy, nuclear permeability assays in C. elegans embryos |
The Journal of cell biology |
Medium |
32271860
|
| 2022 |
Cardiac-specific deletion of Lemd2 in mice causes nuclear envelope deformations, extensive DNA damage, apoptosis, and death shortly after birth. Knockin mice carrying the human p.L13R mutation develop dilated cardiomyopathy and cardiac fibrosis. AAV-mediated Lemd2 gene therapy rescued cardiac function in knockin mice, establishing a direct causal link between LEMD2 loss and DNA damage-dependent cardiomyopathy via p53 activation. |
Conditional cardiac knockout mouse, knockin mouse model (p.L13R), AAV gene therapy rescue, immunostaining for DNA damage markers (γH2AX), apoptosis assays, p53 activation analysis |
The Journal of clinical investigation |
High |
36377660
|
| 2023 |
The p.L13R mutation in the LEM domain of LEMD2 disrupts the interaction between LEMD2 and BAF (barrier-to-autointegration factor), which is required to initiate the nuclear envelope rupture repair process. Mutant cardiomyocytes show impaired nuclear envelope rupture repair, cytoplasmic leakage of DNA repair factor KU80, increased DNA damage, recruitment of cGAS to nuclear membrane/micronuclei, and activation of the cGAS/STING/IFN pathway promoting premature senescence. |
CRISPR/Cas9 knockin mouse and cell model, co-immunoprecipitation (LEM2-BAF interaction), nuclear envelope rupture assays under electrical stimulation and substrate stiffness, immunofluorescence for cGAS/KU80/γH2AX, STING pathway activation assays |
Circulation research |
High |
36656972
|
| 2023 |
In S. pombe, SUMOylation of Lem2 acts as a regulatory switch balancing its roles in centromere clustering versus heterochromatin silencing. Hyper-SUMOylation of Lem2 (caused by delocalizing the SUMO protease Ulp1 from the nuclear envelope) impairs centromeric silencing but enhances centromere clustering; both effects are at least partially dependent on Lem2 SUMOylation. |
Genetic manipulation of SUMO protease Ulp1 localization, epistasis analysis with lem2 mutants, centromere clustering assays, silencing reporter assays in S. pombe |
Journal of cell science |
Medium |
37970674
|
| 2019 |
In S. pombe, Lem2 acts as a barrier to membrane flow between the nuclear envelope and the ER; deletion of Lem2 increases membrane flow into and out of the nuclear envelope in response to changes in membrane synthesis and nucleocytoplasmic transport, altering nuclear size. The ER protein Lnp1 acts as a secondary barrier, functionally compensating for loss of Lem2. |
Fluorescence microscopy of nuclear size in lem2-deletion cells, genetic epistasis (lem2 lnp1 double mutant), membrane flow assays, nuclear size quantification in S. pombe |
Nature communications |
Medium |
31015410
|
| 2018 |
In S. pombe, Lem2 is retained at the nuclear envelope through its interaction with Bqt4; loss of Bqt4 causes exclusive accumulation of Lem2 at the spindle pole body (SPB). The N-terminal nucleoplasmic region of Lem2 has affinity for both Bqt4 and the SPB in a competitive manner, while the C-terminal region suppresses lem2 bqt4 synthetic lethality. |
Genetic epistasis (lem2 bqt4 double mutant synthetic lethality), fluorescence microscopy of Lem2 localization in bqt4-deletion cells, domain deletion/truncation analysis in S. pombe |
Genes to cells : devoted to molecular & cellular mechanisms |
Medium |
29292846
|
| 2022 |
S. pombe Lem2 coordinates nuclear exosome-mediated RNA degradation at the nuclear periphery. Lem2 deletion causes accumulation of RNA precursors and meiotic transcripts. Lem2 does not directly bind RNA but interacts with the exosome-targeting MTREC complex and its human homolog PAXT to promote RNA recruitment to the nuclear periphery. This pathway is regulated by nutrient availability. |
RNA sequencing (accumulation of RNA precursors in lem2Δ), co-immunoprecipitation (Lem2-MTREC/PAXT interaction), fluorescence microscopy of exosome substrate localization, genetic deletion analysis in S. pombe |
Nature structural & molecular biology |
High |
36123402
|
| 2015 |
In S. pombe, Lem2 facilitates Rad3 (ATR)-mediated replication checkpoint signaling for Cds1 (CHK2) activation in response to hydroxyurea (nucleotide depletion). In lem2-deletion cells, all Rad3-dependent phosphorylations critical for replication checkpoint signaling are severely compromised, causing aberrant mitosis and drug sensitivity. The DNA damage checkpoint remains largely intact, indicating Lem2 specifically facilitates replication stress checkpoint signaling. |
Genetic deletion (lem2Δ), Western blotting for checkpoint kinase phosphorylation (Rad3-dependent substrates, Cds1 activation), hydroxyurea sensitivity assay, DNA damage checkpoint analysis in S. pombe |
Cellular signalling |
Medium |
26746798
|
| 2020 |
SATB2 (a chromosomal scaffolding protein) physically interacts with LEMD2 (inner nuclear membrane protein) in pyramidal neurons, and together they orchestrate activity-dependent nuclear shape changes and gene expression. LEMD2 depletion in cortical neurons affects neuronal activity-dependent regulation of multiple rapid and delayed primary response genes, similar to SATB2 ablation. The activity-driven nuclear envelope plasticity also requires the ESCRT-III/VPS4 complex. |
Co-immunoprecipitation (SATB2-LEMD2 interaction), siRNA knockdown of LEMD2 in cortical neurons, RNA-seq of activity-regulated genes, in vivo nuclear shape assay (novel environment exposure), immunofluorescence |
The EMBO journal |
Medium |
33319920
|
| 2010 |
In C. elegans, LEM-2 (LEMD2 ortholog) associates with large chromatin domains on chromosome arms (but not centers) via ChIP, with these domains characterized by high repeat density, low gene density, and H3K27me3 enrichment. A translocated chromosome arm retains LEM-2 association, indicating local chromatin properties (not chromosomal position) primarily determine nuclear membrane interaction. |
Chromatin immunoprecipitation followed by sequencing (ChIP-seq) in C. elegans embryos, chromosome translocation analysis |
Genome biology |
Medium |
21176223
|
| 2023 |
Lem2 is essential for cardiac development by protecting cardiomyocyte nuclei from mechanical forces of muscle contraction. Cardiac-specific Lem2 knockout mice show DNA damage, nuclear rupture, and apoptosis driven by muscle contraction (ameliorated by inhibiting myosin contraction and L-type calcium channels). Partial Lem2 depletion (~45%) in adult cardiomyocytes does not cause overt cardiac dysfunction up to 18 months. |
Conditional cardiac knockout (embryonic and inducible adult), 3D high-resolution episcopic microscopy, RNA-seq, myosin inhibitor/calcium channel blocker rescue, echocardiography, nuclear rupture assays |
Cardiovascular research |
High |
37067297
|
| 2025 |
LEM2, together with BAF, forms a multivalent protein-DNA co-condensate (surface hydrogel) at the nuclear surface that mechanically reinforces the nuclear envelope and protects DNA under mechanical stress. Under optical tweezer load, the LEM2-BAF assembly induces DNA stiffening beyond its melting point, dependent on LEM2's intrinsically disordered region (IDR). LEM2 IDR-IDR interactions contract the surface hydrogel and introduce pre-stress in the lamin network. Disruption of the surface hydrogel increases DNA damage and micronuclei formation during nuclear deformation. |
Optical tweezers (single-molecule force spectroscopy), AFM indentation, in vitro reconstitution of LEM2-BAF co-condensates, domain mutagenesis (IDR deletion), live-cell assays for DNA damage and micronuclei |
bioRxivpreprint |
Medium |
bio_10.1101_2025.05.21.655270
|