Requirement for STAT3 and its target, TFCP2L1, in self-renewal of naïve pluripotent stem cells in vivo and in vitro

Abstract

We previously demonstrated gradual loss of epiblast during diapause in embryos lacking components of the LIF/IL6 receptor. Here, we explore requirement for the downstream signalling transducer and activator of transcription, STAT3 and its target, TFCP2L1, in maintenance of naïve pluripotency. Unlike conventional markers, such as NANOG, which remains high in epiblast until implantation, both STAT3 and TFCP2L1 proteins decline during blastocyst expansion, but intensify in the embryonic region after induction of diapause, as observed visually and confirmed using our image analysis pipeline, consistent with our previous transcriptional expression data. Embryos lacking STAT3 or TFCP2L1 underwent catastrophic loss of most of the inner cell mass during the first few days of diapause, implicating involvement of signals in addition to LIF/IL6 for sustaining naïve pluripotency in vivo. By blocking MEK/ERK signalling from the morula stage we could derive embryonic stem cells with high efficiency from STAT3 null embryos, but not those lacking TFCP2L1, suggesting a hitherto unknown additional role for this essential STAT3 target in transition from embryo to embryonic stem cells in vitro.

Evidence implicating sequential commitment of the founder lineages in the human blastocyst by order of hypoblast gene activation

“…The Hoechst 33342 channel was used for nuclei segmentation in three dimensions using ZeroCostDL4Mic StarDist via Google colaboratory ( Schmidt et al, 2018 ; Weigert et al, 2018 ). For details on software training for embryo images, see Kraunsoe et al (2023) .…”

A Simplified and Effective Approach for the Isolation of Small Pluripotent Stem Cells Derived from Human Peripheral Blood

“…MTHFD1 is an enzyme involved in folate metabolism [ 115 , 116 , 117 ], and although it was reported as a potential stem cell marker by Maguire et al and Bhattacharya et al [ 51 , 118 ], there is no other knowledge in regard to its role in stem cell pluripotency, while its polymorphisms have been associated with therapeutic response to methotrexate in childhood acute lymphoblastic leukemia [ 119 , 120 , 121 ]. STAT3 is well known as a transcription factor for its role in the regulation of the self-renewal of embryonic stem cells [ 122 , 123 , 124 ], suggesting that its expression in SBSCs may indeed promote their self-renewal.…”

Identification of m6A methylation-related genes in cerebral ischaemia‒reperfusion of Breviscapus therapy based on bioinformatics methods

“…However, studies have shown that Tfcp2l1 is a downstream target of the canonical Wnt/β-catenin, STAT3 and FGF/MEK signalling pathways and plays a pivotal role in promoting embryonic stem cell self-renewal [ 34 , 35 ]. In addition, the lower Kcns3 levels provide a new molecular mechanism of neuron dysfunction in schizophrenia, which encodes potassium channel-associated subunits [ 36 ].…”