FTIR spectral signatures of mouse antral oocytes: Molecular markers of oocyte maturation and developmental competence

► FTIR microspectroscopy has been applied to the study of single Surrounded Nucleolus (SN) and Not Surrounded Nucleolus (NSN) murine oocytes at three stages of their maturation. ► The two types of oocytes displayed differences in the lipid, protein, and in the nucleic absorption regions. ► The most significant differences concerned the IR bands reflecting transcriptional activity and polyadenylation. ► The multivariate statistical analysis allowed to identify the maturation stage where the separation between the two types of oocytes takes place.