Truncated variants of aptamers selected against VEGF.

Dashed lines correspond to the nucleotides that were removed from hVaps. Truncated variants of hVap1 contains 2 nucleotides belonging to the 5′ constant region to provide structural flexibility to the variable region when bound to streptavidin. hVap1_Stem contains the first and second stem-loops without the third stem-loop sequence inserted into the second stem-loop. hVap1_SST contains the first and shortened second stem-loop sequence. hVap2_T2160 contains nucleotides 21–60 of the full-length 100-nt hVap2.

虚线代表自hVaps中移除的核苷酸。hVap1的截短变体包含2个源自5'恒定区（5′ constant region）的核苷酸，以便在与链霉亲和素（streptavidin）结合时，为其可变区提供结构柔性。hVap1_Stem包含第一和第二茎环结构（stem-loop），未将第三茎环序列插入至第二茎环结构内。hVap1_SST包含第一茎环序列与经截短的第二茎环序列。hVap2_T2160包含全长100核苷酸的hVap2的第21至60位核苷酸。