MemPype: a pipeline for the annotation of eukaryotic membrane proteins

Andrea Pierleoni1, Valentina Indio, Castrense Savojardo

  • 1Externautics s.p.a.-Bioinformatics, Via Fiorentina 1, 53100 Siena, Italy. andrea.pierleoni@externautics.com

Insights

MemPype is a novel Python pipeline for predicting eukaryotic membrane protein features. It accurately identifies signal peptides, GPI anchors, and subcellular localization, improving membrane protein annotation.

Area of Science:

  • Bioinformatics
  • Computational Biology
  • Molecular Biology

Background:

  • Accurate prediction of membrane protein characteristics is crucial for understanding cellular functions.
  • Existing tools often lack comprehensive analysis for signal peptides, GPI anchors, and subcellular localization.
  • Eukaryotic membrane protein annotation requires integrated approaches for reliable classification.

Purpose of the Study:

  • To develop and present MemPype, an integrated Python pipeline for eukaryotic membrane protein annotation.
  • To enhance the prediction accuracy of signal peptides, GPI anchors, and subcellular localization.
  • To provide a user-friendly web server for computational analysis of membrane proteins.

Main Methods:

  • Integration of established methods: SPEP (signal peptides), PredGPI (GPI anchors), ENSEMBL (all-alpha membrane topology).
  • Inclusion of MemLoci for discriminating subcellular localization: 'cell membrane', 'internal membranes', 'organelle membranes'.
  • Utilizing homology-based inheritance and computational predictions, including homology searches and filtering for specific protein features.

Main Results:

  • MemLoci achieved 70% accuracy and 0.50 GCC on a homology-unbiased validation set, outperforming other predictors.
  • The pipeline accurately predicts signal peptides, GPI anchors (0.8% FPR), and all-alpha membrane topology (<1% FPR).
  • Homology searches (≥50% identity, ≥50% coverage) aid in identifying membrane-associated proteins and localization tags.

Conclusions:

  • MemPype offers a robust and accurate pipeline for comprehensive eukaryotic membrane protein annotation.
  • The integrated approach, particularly MemLoci, significantly improves subcellular localization prediction.
  • The available web server facilitates accessibility and application of these advanced computational tools in biological research.

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