biostudies-literatureMiskiewicz EINatural Sciences and Engineering Research Council of CanadaCanada Foundation for Innovation149-162https://www.ebi.ac.uk/biostudies/studies/S-EPMC9922239biostudies-literatureUnknown159(2)Uterine myocytes during pregnancy proceed through a series of adaptations and collectively transform into a powerfully contractile tissue by term. Previous work has indicated that members of the heat shock protein (HSP) B family of stress proteins are associated with the process of adaptation and transformation. Utilizing immunoblot analyses, widefield epifluorescence and total internal reflection (TIRF) microscopy, this study investigated the temporal and spatial detection of HSPB1 phosphorylated on serine-86 (pS86-HSPB1) in rat myometrium during pregnancy, the role of uterine distension in regulation of pS86-HSPB1, and the comparative localization with pS15-HSPB1 in rat myometrial tissue as well as in an immortalized human myometrial cell line. Immunoblot detection of pS86-HSPB1 was signHistochemistry and cell biologyPhosphoserine-86-HSPB1 (pS86-HSPB1) is cytoplasmic and highly induced in rat myometrium at labour.PMC992223932512RGPIN-2017-04951Miskiewicz EIOlaloku AMacPhee BKMacPhee DJfalsePhosphoserine-86-HSPB1 (pS86-HSPB1) is cytoplasmic and highly induced in rat myometrium at labour.Uterine myocytes during pregnancy proceed through a series of adaptations and collectively transform into a powerfully contractile tissue by term. Previous work has indicated that members of the heat shock protein (HSP) B family of stress proteins are associated with the process of adaptation and transformation. Utilizing immunoblot analyses, widefield epifluorescence and total internal reflection (TIRF) microscopy, this study investigated the temporal and spatial detection of HSPB1 phosphorylated on serine-86 (pS86-HSPB1) in rat myometrium during pregnancy, the role of uterine distension in regulation of pS86-HSPB1, and the comparative localization with pS15-HSPB1 in rat myometrial tissue as well as in an immortalized human myometrial cell line. Immunoblot detection of pS86-HSPB1 was sign2023-01-01T00:00:00Z2023 Feb2025-04-22T18:25:51.791Z2025-04-06T02:24:51.799ZS-EPMC99222393626011210.1007/s00418-022-02158-1