Dark Proteome of Newly Emerged SARS-CoV-2 in Comparison with Human and Bat Coronaviruses

Rajanish Giri; Taniya Bhardwaj; Meenakshi Shegane; Bhuvaneshwari R. Gehi; Prateek Kumar; Kundlik Gadhave

The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.03.13.990598 doi: bioRxiv preprint of Human SARS than to ORF7b of Bat CoV, showing sequence identities of 81.40% and 79.07%, respectively (see Figure 11D ). As can be observed from Table 1 , our disorder predisposition analyses resulted in the overall PPID for ORF7a proteins of 1.65% for SARS-CoV-2, 0.82% for Bat CoV and 0.82% for Human SARS CoV. Mean PPIDs estimated for ORF7b proteins are 9.30% for SARS-CoV-2, 4.55% for Bat CoV and 4.55% Human SARS CoV. Figures 10A, 10B , and 10C represent the residues predisposed for disorder in ORF7a proteins of SARS-CoV-2, Human SARS CoV, and Bat CoV, respectively. Table 2 shows that ORF7a protein is expected to have several MoRFs indicating the potential involvement of this protein in disorder-dependent proteinprotein interactions. At the N-terminus, we observed one MoRF region (residues 1-10) with the help of DISOPRED3 in all three viruses. In addition to protein binding regions, ORF7a also contains several RNA and DNA binding residues. Analysis also represents, ORF7b proteins from all three viruses have low disorder content, likewise, they are not predicted to contain any MoRF by any of the predictors used in this study ( Table 2, Supplementary Table 7 and 8). Although the ORF7b does not contain protein-binding regions, it was found to contain nucleotide (RNS and DNA) binding regions in the protein Figures 11A, 11B , and 11C depict the residues predisposed for disorder in ORF7b proteins of SARS-CoV-2, Human SARS CoV, and Bat CoV, respectively. According to our analysis, both proteins in all three studied coronaviruses have a mostly ordered structure.