RESUMEN
Natural products (NPs), especially those from traditional herbal medicines, can evidently modulate human gene expression at multiple levels, leading to a wide diversity of bioactivities. Although numerous bio-functions of NPs for human body have been found, there is little understanding about how NPs achieve it, as less attention was drawn to the definite mechnism by which NPs regulate gene expression. Furthermore, based on the rapidly advancing knowledge of mechanisms for gene regulation in recent years, newly-understood mechanisms, such as post-transcriptional regulation, are found to be involved in NP-elicited bio-effects, providing a new perspective on understanding the role of NPs in gene expression. Therefore, in the current review, we summarize the function of NPs in gene expression from the perspectives of transcriptional, post-transcriptional, and post-translational regulation, which will reinforce the understanding of NP-induced effects in gene expression and facilitate the exploration of more NPs with potential therapeutic effects.
Asunto(s)
Humanos , Productos Biológicos/farmacología , Expresión Génica , Regulación de la Expresión GénicaRESUMEN
The CP15 and CP23 surface proteins on the sporozoite of Cryptosporidium parvum are major protective antigens. The recombinant plasmid pET28-15-23 was constructed based on the plasmids pMD18-T-15 and pMD18-T-23 with two pairs of specific primers using DNA recombinant technique. In the primers, a synthetic linker sequence encoding a peptide (G-G-S) was designed. After identification, the recombinant plasmids were transformed to component cells of Escherichia coli BL21 (DE3). The positive strain containing the recombinant plasmid could express a specific fusion protein (CP15-23, MW approximately 25 kDa) induced by IPTG. The fusion protein could be recognized by the positive serum of mice infected with Cryptosporidium parvum oocysts specifically. The BALB/c mice were immunized with 80 microg of CP15-23 protein 4 times at 2 week intervals. The mice produced specific antibodies that responded to the lysate of Cryptosporidium parvum oocysts and could prevent Cryptosporidium parvum infection. The results indicated that the recombinant fusion protein CP15-23 would be used as a candidate antigen to prevent cryptosporidiosis.