ABSTRACT
In early 1990s, several proteins were shown to depend on additional stretches of polypeptide (termed as prosequence/prodomain) for their folding. These regions of the protein were often termed as IMCs (Intra Molecular Chaperones), since they would be cleaved from the mature folded protein eventually. Such proteins were hypothesized to face a kinetic barrier to their folding, which was probably lowered by the prosequences. In last three decades, numerous examples of such proteins have accumulated in literature. Yet, no study has been reported so far attempting to understand the evolutionary differences and similaritess of such proteins. Till date such proteins are continued to be treated as anomalous variants, rather than as representatives of any alternate protein folding strategy. Do such proteins have any distinctive structural facets OR typical biological roles, necessitating an unconventional strategy of protein folding? Do prosequences carry any unique or conserved features that are essential to their function? ProSeqAProDb: ProSequence Assisted Protein Database, (which can be accessed at https://proseqaprodb.mkulab.in) was built as a comprehensive database, to systematically study such proteins along with their pro-sequences. The database currently contains 2140 prosequence assisted proteins (1848 eukaryotic, 255 bacterial, 24 viral and 13 archaeal proteins), from 690 organisms later categorised into 960 families. We envisage that the availability of this curated dataset will enable the researchers worldwide to further their investigation in the origin, importance and evolution of such proteins, leading to better understanding of the protein folding process as a whole.