The TSS mapping protocol uses TAP or “Tobacco Acid Pyrophosphatase”, an enzyme that converts the 5′ PPP ends of native RNAs into 5′ P ends, compatible with adapter ligation.
The study is performed by comparing the sequencing results of the 5′ ends of RNAs treated or not with TAP. Without TAP, sequencing will give access to all RNAs (messenger RNAs mature or in process of degradation ) except those with native 5′ ends. After TAP treatment, the same sequences will be obtained, with the additional sequences of the native RNA (S Cho et al.).
