MTMR3 Knockout HAP1 Cell Line

The choice depends on the experimental question. MTMR3 (myotubularin-related protein 3) is a myotubularin-family phosphatidylinositol phosphatase with limited functional characterization compared to MTM1 (myotubularin). The Knockout line is appropriate for asking whether MTMR3 is required for predicted PI(3)P and PI(3,5)P2 hydrolysis activities — MTMR3 is one of 14 myotubularin family members (MTM1, MTMR1-14) with various catalytic activities and substrate preferences, regulating endosomal phosphoinositide pools. Overexpression is useful for studying MTMR3 substrate preferences in heterologous expression contexts. For myotubularin family research, the EDITGENE MTMR3 Knockout in HAP1 enables characterization of MTMR3-specific contributions to phosphoinositide metabolism. MTMR4 (heterodimer partner of MTMR3) expression analysis aids interpretation given functional cooperation. Rescue with wild-type or phosphatase-dead MTMR3 enables structure-function studies. The knockout is valuable for studying MTMR3-related cellular processes including autophagy regulation.

Primary applications: • PI(3)P/PI(3,5)P2 quantification: phosphoinositide HPLC or biosensor imaging analysis in MTMR3-null cells. • Autophagy regulation: LC3-II accumulation and autophagic flux given PI(3)P's role in autophagosome formation and MTMR3's reported autophagy regulatory role. • Myotubularin family comparative studies: MTM1, MTMR1-2, MTMR4 expression analysis to interpret MTMR3-specific functions. • Endosomal trafficking: cargo trafficking through MTMR3-dependent endosomal compartments. EDITGENE recommends this model for researchers investigating myotubularin family phosphatase biology and PI(3)P-dependent membrane trafficking.

Yes. MTMR3 rescue experiments require attention to phosphatase architecture: • Construct design: use a codon-modified MTMR3 sequence with a small C-terminal tag (FLAG, HA). MTMR3 has N-terminal PH-GRAM domain, phosphatase domain (CX5R motif), coiled-coil, and C-terminal FYVE domain — preserve all elements. • Phosphatase-dead rescue: catalytic cysteine mutation in the CX5R motif abolishes phosphatase activity and is the standard specificity control. • MTMR4 partnership: MTMR3-MTMR4 heterodimer formation analysis given functional cooperation. • Functional readout: rescue should restore PI(3)P and PI(3,5)P2 hydrolysis and downstream membrane trafficking phenotypes. HAP1-specific considerations: • Diploidization: HAP1 cells gradually diploidize during extended culture — confirm ploidy by flow cytometry at the time of phenotypic assay. • Integration site sensitivity: position effects on transgene expression are more pronounced in near-haploid backgrounds; generating multiple independent rescue clones is strongly recommended. • Transduction efficiency: HAP1 transduces with lentivirus at moderate efficiency — increase MOI compared to standard immortalized lines.