Integrative single-cell transcriptomic analysis unveils alternative polyadenylation modulation in the mouse mammary gland

GARCIA SOLA MARTÍN; MONTANI MERCEDES; STEDILE MICAELA; BECKERMAN INÉS; COSO OMAR; EDITH C KORDON

CABA

Simposio; BA-BCS 2021; 2021

The mammary gland (MG) is a highly dynamic organwhich undergoes periods of expansion, differentiation andcell death in each reproductive cycle. Single cell RNA-seq(scRNA-seq) analyses have contributed to understand thecellular and transcriptional heterogeneity of this complextissue. Alternative polyadenylation (APA) generates diversemRNA isoforms, which contributes to transcriptomediversity and gene expression regulation by affectingmRNA stability, translation and intracellular localization.This study is based on publicly available data from 53,686individual cells obtained during mammary post-natal development,from puberty to post-involution. The originaldata-sets correspond to three foundational reports thathave explored the MG cell populations throughout developmentat single-cell level using 3′tag-based scRNA-seq.This feature of the sequencing protocol allowed us toanalyze APA patterns in the mammary epithelial cells(MECs). Our results show relevant changes in gene familiesassociated with mRNA processing, such as hnRNP,Eif and Srsf, in different mammary cell linages throughoutthe post-natal phases. Besides, APA modulation is alsoobserved in key mRNAs for MG development and function,as Egfr1 and Prlr, which encode EGF receptor andProlactin receptor, respectively In summary, this studyreveals that APA may provide a new control layer ongene expression regulation in MECs throughout pubertyand adulthood.