Proteins with expanded polyglutamine (PolyQ) repeats are involved in human neurodegenerative diseases, via a gain-of-function mechanism of neuronal toxicity involving protein conformational changes that result in the formation and deposition of -sheet rich aggregates. Aggregation is dependent on context, specifically the properties of the host protein such as domain architecture and location of the repeat tract. In order to explore this relationship in greater detail, here we describe PolyQ 2.0, an updated database that provides a comprehensive knowledgebase for human polyQ proteins. Specifically, the database details domain context information, protein structural and functional annotation, single point mutation, predicted disordered regions, protein-protein interaction partners, metabolic/signaling pathways, post-translational modification sites and evolutionary information. Multiple database functionalities have also been added, including database search with multiple keywords, and new entry submission. Currently the database contains 9 reviewed disease-associated polyQ proteins, 105 reviewed non-disease polyQ proteins and 146 un-reviewed polyQ proteins. We envisage that this updated database will be a useful resource for functional and structural investigation of human polyQ proteins.

    If you find PolyQ 2.0 useful, please cite us:
   Chen Li, Jeremy Nagel, Steve Androulakis, Christopher J. Lupton, Jiangning Song and Ashley M. Buckle. PolyQ 2.0: an Improved Version of PolyQ, a Database of Human Polyglutamine Proteins. Database, 2016, DOI:10.1093/database/baw021.

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    (5) The purpose of this database is to provide biological annotations for human polyQ proteins. Such biological annotations may not be complete and are subject to frequent updates. Therefore it is strongly recommended that one should seek for multiple sources/databases when examining the protein functions and structures.