| 1999 |
MER3 (yeast ortholog of HFM1) encodes a DExH-box type helicase required for the transition of meiotic double-strand breaks (DSBs) to later recombination intermediates and for crossover control; mer3 mutants show hyperresected DSBs persisting late in meiosis, reduced crossover frequencies, and random crossover distribution leading to non-disjunction. |
Genetic analysis of mer3 deletion mutants in S. cerevisiae, meiotic DSB and recombination intermediate analysis |
The EMBO journal |
High |
10523314
|
| 2001 |
Purified MER3 protein is a DNA helicase with ATPase activity stimulated by single- or double-stranded DNA (kcat ~500/min); it unwinds DNA in the 3' to 5' direction and requires RPA (replication protein A) to displace long DNA fragments by preventing re-annealing of single-stranded products. |
In vitro biochemical assays with purified MER3 protein: ATPase assay, DNA helicase displacement assay, directionality assay with ssDNA circular substrates, RPA stimulation assay |
The Journal of biological chemistry |
High |
11376001
|
| 2002 |
Mer3 helicase activity is required for meiotic crossing over: the mer3G166D mutation reduces helicase activity to <1% of wild-type without affecting DNA binding, while mer3K167A eliminates ATPase activity; both mutations cause defects in DSB transition, decreased crossing over, and reduced crossover interference. |
Site-directed mutagenesis of conserved helicase motif residues, purified mutant protein biochemical assays (ATPase, helicase, DNA binding), genetic analysis in S. cerevisiae meiosis |
Molecular and cellular biology |
High |
11971962
|
| 2002 |
Purified MER3 helicase can unwind Holliday junctions (with 25-bp arms and blunt ends) as well as blunt-ended and 5'-overhang dsDNA substrates; unwinding of the 3'-overhang substrate requires ≥6 unpaired bases for initiation, and Holliday junction unwinding efficiency is influenced by Mg2+ concentration. |
In vitro helicase assays with purified MER3 and defined DNA substrates including synthetic Holliday junctions, varying Mg2+ conditions |
The Journal of biological chemistry |
High |
12039965
|
| 2004 |
Mer3 helicase stimulates 3'→5' heteroduplex extension by Rad51 during DNA strand exchange, but blocks 5'→3' heteroduplex extension; Mer3 does not initiate DNA pairing but stabilizes nascent joint molecules to permit capture of the second processed end of a DSB, a step required for crossover product formation. |
In vitro DNA strand exchange assays with purified Mer3 and Rad51 proteins, directional heteroduplex extension assays |
Cell |
High |
15066281
|
| 2006 |
Human HFM1 encodes a predicted 172 kDa protein with seven consecutive DEXH-box helicase motifs at the N-terminus and a single putative zinc finger motif at the C-terminus, sharing domain architecture with yeast Mer3; its transcript is preferentially expressed in testis and ovary (germ-line specific). |
cDNA cloning, sequence analysis, RT-PCR tissue expression analysis |
DNA sequence : the journal of DNA sequencing and mapping |
Medium |
17286053
|
| 2013 |
Mouse HFM1 is required for normal crossover formation and complete synapsis during meiosis: Hfm1−/− spermatocytes show altered MSH4 chromosomal localization, drastically reduced MLH1 foci (crossover markers), reduced chiasmata, and incomplete synaptonemal complex extension, with arrest and apoptosis at diakinesis. |
Conditional knockout mouse model, cytological analysis, immunofluorescence for MSH4 and MLH1 foci, chiasma counting, synaptonemal complex analysis |
PLoS genetics |
High |
23555294
|
| 2017 |
Mer3 helicase physically interacts with the MutLβ complex (Mlh1-Mlh2) and recruits it to meiotic recombination hotspots independently of mismatch recognition; this recruitment limits gene conversion tract lengths genome-wide without affecting crossover formation. Both purified Mer3 and MutLβ preferentially recognize D-loop structures. Surprisingly, Mer3 helicase catalytic activity does not influence gene conversion tract length, revealing a non-catalytic role of Mer3. |
Co-immunoprecipitation, mass spectrometry, genome-wide sequencing of gene conversion tracts, in vitro binding assays with purified proteins and D-loop substrates, helicase-dead mutant analysis |
eLife |
High |
28051769
|
| 2020 |
In mouse oocytes, Hfm1 localizes not only to the cytoplasm but also accumulates at spindle poles where it co-localizes with the Golgi marker GM130; conditional knockout of Hfm1 in oocytes causes loss of GM130 and p-MAPK from spindle poles, abnormal spindle assembly, misaligned chromosomes, loss of cortical actin cap, and failed polar body extrusion. |
Conditional knockout mouse model (cKO from primordial follicle stage), immunofluorescence co-localization with GM130 and p-MAPK, spindle and chromosome analysis |
Cell death & disease |
Medium |
32606310
|
| 2022 |
Biallelic HFM1 variants in humans cause non-obstructive azoospermia with meiotic arrest at metaphase I due to impaired crossover formation; mouse models carrying equivalent variants recapitulate the meiotic defects, showing reduced HFM1 foci on chromosome axes and varying degrees of synapsis and crossover formation defects in a dose-dependent manner. |
Whole-exome sequencing in patients, histological and immunofluorescence analysis of testicular sections, mouse knock-in models carrying patient-equivalent variants, HFM1 foci quantification on chromosome spreads |
Human reproduction (Oxford, England) |
High |
35526155
|
| 2024 |
HFM1 deficiency in mouse oocytes promotes ubiquitination and FBXW11-mediated degradation of FUS protein, alters intranuclear localization of FUS, and modulates expression of meiotic and oocyte development-related genes through BRCA1; Hfm1 KO oocytes arrest at the pachytene stage with impaired DSB repair and disrupted synapsis. |
Conditional knockout mouse model, co-immunoprecipitation, ubiquitination assay, immunofluorescence for FUS localization and synapsis markers, gene expression analysis |
Biological research |
Medium |
38822414
|
| 2024 |
HFM1 is involved in intercellular directional transport through germ cell intercellular bridges via the RAC1/ANLN/E-cadherin signaling pathway during oocyte differentiation; this function is required for organelle enrichment from sister germ cells and primordial follicle formation in mice. |
Conditional knockout mouse model, immunofluorescence, live imaging of intercellular bridge transport, pathway analysis of RAC1/ANLN/E-cad signaling |
Cellular and molecular life sciences : CMLS |
Medium |
39725823
|
| 2026 |
RPA directly interacts with Mer3 (HFM1 in humans) through a conserved and specific interface identified by cross-linking mass spectrometry and AlphaFold2 structural modelling; this interaction is conserved between yeast Mer3 and human HFM1. Direct RPA interaction is required for Mer3 helicase processivity under low DNA tension conditions (demonstrated by single-molecule magnetic tweezers). A mer3 mutant deficient in RPA binding shows reduced crossover frequencies, accumulation of unresolved recombination intermediates, and weakened recruitment to DSB sites. |
Co-immunoprecipitation (yeast and human), cross-linking mass spectrometry, AlphaFold2 structural modelling, single-molecule magnetic tweezers assays, genome-wide localization (ChIP-seq equivalent), genetic analysis of RPA-binding-deficient mer3 mutant |
Nature communications |
High |
41851108
|
| 2026 |
A pathogenic homozygous HFM1 mutation causes aberrant mRNA splicing producing a protein variant that fails to localize to the nucleus; nuclear exclusion of HFM1 leads to widespread transcriptional dysregulation, failure of zygotic genome activation (ZGA), aberrant retention of H3K27me3, and consequent embryonic arrest. Wild-type but not mutant HFM1 mRNA rescued embryonic defects in a mouse knockdown model. |
Minigene splicing assay, immunofluorescence and confocal imaging for protein localization, RNA-seq, epigenetic profiling (H3K27me3), functional rescue experiments in mouse embryos with WT vs. mutant HFM1 mRNA |
Human reproduction (Oxford, England) |
Medium |
41423819
|