ABSTRACT
Polypeptides play a vital role in physiological processes of life. The pharmacological and medical value of polypeptides has attracted the attention of researchers in recent years. Aptamers are short, single stranded DNA or RNA which developed by an in vitro process called systematic evolution of ligands by exponential enrichment ( SELEX ) . Aptamers can bind targets with high affinity and specificity. Hence, aptamer is also called "chemical antibody" or "chemist's antibody". To date, there are two main application aspects for polypeptides-targeted aptamers. First, aptamer can be used as specific affinitive elements based on their ability of recognition, which would be applied to polypeptides detection or imaging. The other one is that aptamer can also be used as antagonists based on their ability of inhibiting, which can restrict the activity of polypeptides and block the downstream signaling pathways in vivo, thus can be used to treat the disease associated with polypeptides. In this review, we summarize the numbers of polypeptides-targeted aptamers and the related applications in vitro and in vivo. Current issues and development trends throughout the screening, characterizing and applying of polypeptides-targeted aptamers are also discussed.