MPHOSPH6

MPHOSPH6 functions in ribosome biogenesis, where it contributes to recruitment of the RNA exosome to pre-rRNA (PMID:29069794). Functional genetic variants at the 16q23.3 locus regulate MPHOSPH6 expression and protein function, linking it to telomere length and lung cancer risk (PMID:42152146). Its mRNA is a target of miR-146b-5p, placing it under post-transcriptional control (PMID:30145833). Beyond these associations, direct biochemical characterization of its enzymatic or structural mechanism has not been established in the available corpus.

1. 2017 Low

   Established a functional role for MPHOSPH6 in ribosome biogenesis by linking it to recruitment of the RNA exosome to pre-rRNA.

   Evidence Functional annotation cited as background within a genetic association study

   PMID:29069794

   Open questions at the time

   • Claim is stated as background, not experimentally demonstrated in this study
   • No direct biochemical assay of exosome recruitment shown
   • No structural or domain-level mechanism defined
2. 2018 Low

   Identified MPHOSPH6 mRNA as a target of miR-146b-5p, indicating post-transcriptional regulation of its expression.

   Evidence Inducible miR-146b-5p overexpression in PH5CH8 hepatocytes followed by RNA-Seq and validation

   PMID:30145833

   Open questions at the time

   • No direct binding or reporter assay establishing a physical miRNA-mRNA interaction described
   • Single cell-type context
   • Functional consequence of repression on ribosome biogenesis not tested
3. 2026 Medium

   Demonstrated that variants at 16q23.3 regulate MPHOSPH6 expression and protein function, connecting the gene to telomere length and lung cancer risk.

   Evidence Functional assays plus eQTL colocalization and genome-wide meta-analysis

   PMID:42152146

   Open questions at the time

   • Specific functional assay methodology not detailed
   • Mechanism linking MPHOSPH6 to telomere length not resolved
   • Causal protein-level effect on ribosome biogenesis pathway not connected

• The direct molecular and structural mechanism by which MPHOSPH6 acts on the exosome and pre-rRNA, and how this relates to telomere maintenance, remains unresolved.
• No reconstitution of MPHOSPH6-exosome interaction
• No structural model
• Mechanistic link between expression and telomere length undefined