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Introduction: Coronaviruses (CoVs) are naturally found in bats and can occasionally cause infection and transmission in humans and other mammals. Our study aimed to build a deep learning (DL) method to predict the adaptation of bat CoVs to other mammals. Methods: The CoV genome was represented with a method of dinucleotide composition representation (DCR) for the two main viral genes, ORF1ab and Spike. DCR features were first analyzed for their distribution among adaptive hosts and then trained with a DL classifier of convolutional neural networks (CNN) to predict the adaptation of bat CoVs. Results and discussion: The results demonstrated inter-host separation and intra-host clustering of DCR-represented CoVs for six host types: Artiodactyla, Carnivora, Chiroptera, Primates, Rodentia/Lagomorpha, and Suiformes. The DCR-based CNN with five host labels (without Chiroptera) predicted a dominant adaptation of bat CoVs to Artiodactyla hosts, then to Carnivora and Rodentia/Lagomorpha mammals, and later to primates. Moreover, a linear asymptotic adaptation of all CoVs (except Suiformes) from Artiodactyla to Carnivora and Rodentia/Lagomorpha and then to Primates indicates an asymptotic bats-other mammals-human adaptation. Conclusion: Genomic dinucleotides represented as DCR indicate a host-specific separation, and clustering predicts a linear asymptotic adaptation shift of bat CoVs from other mammals to humans via deep learning.
RESUMO
<p><b>OBJECTIVE</b>To observe the effect of bombesin noncytoskeleton form and intracellular free calcium ([Ca2+]i) concentration in PC-3 prostate cancer cell line.</p><p><b>METHODS</b>Immunofluorescent histochemistry (IH) combined with laser scanning confocal microscopy (LSCM) was used to examine the expression of cytokeratin (CK) in PC-3 cells treated with definite concentrations of BBS and observe its effect on cytoskeleton form. Fluo-3/AM fluorescence technique and LSCM were adopted to measure the [Ca2+]i concentration after different concentrations (10(-9), 10(-7) and 10(-5) mol/L) of BBS were added in PC-3 cells.</p><p><b>RESULTS</b>BBS (10(-5) mol/L) stimulated the expression of CK in PC-3 cells and the formation of lamellipodium, and increased the [Ca2+]i concentration, with concentration dependence.</p><p><b>CONCLUSION</b>Definite concentrations of BBS could obviously enhance the [Ca2+] i concentration, CK expression and cytoskeleton morphology of PC-3 cells. The results provide a basis for further studies on the role of BBS in tumour researches as well as in intracellular signal transmission.</p>
