GSM9380073: HeLa, STLC 0 h; Homo sapiens; OTHER
Cells were washed in PBS and resuspended in TRIzol Reagent. All RNA isolations were performed with Phasemaker™ tubes according to the manufacturer's protocol (Invitrogen, A33248). Total RNA was resuspended in water with 4 pg spike-in RNA (equal mixture of in vitro transcribed Fluc and Nluc) per 2 ug total RNA for experiments where spike-in RNA was used for normalization. For each sample, 500 ng total RNA was used for library prep. Sequencing of endogenous mRNA poly(A) tail lengths in interphase and mitosis was performed with PAL-seq v4 as described in (Xiang & Bartel, 2021).