Based on analysis of NUPs transcripts across normal tissues, NUP62 expression levels were prominent in stratified epithelia tissues. nuclear transport. We further find that differentiation\inducible Rho kinase reduces the conversation between NUP62 and Np63 by phosphorylation of phenylalanineCglycine regions of NUP62, attenuating Np63 nuclear import. Our results characterize NUP62 as a gatekeeper for Np63 and uncover its role in the control of cell fate through regulation of Np63 nuclear transport in SCC. in up to TNFRSF10D 30% of tumors, with overexpression of its mRNA in the majority of SCCs 1, 2, 3, 4. during embryogenesis resulted in the absence of skin and limbs 5, 6. contains two different promoters to drive two unique isoform classes either with or without N\terminal transactivation domain name, TAp63 and Np63, respectively 9, 10, 11. In addition, both TAp63 and Np63 have three variants with different C\termini (, , and ) generated by option splicing 9, 10, 11. Np63 is the prominent isoform in adult epidermis 7, 13, 14, where it contributes to self\renewal ability or stemness [5, 6, 7, 8,15, 16, 17]. Of notice, pharmacological inhibition of ROCK, a differentiation\inducible serine/threonine kinase 18, 19, resulted in induction of continuous proliferation ability with elevated Np63 expression in keratinocytes 20. In the context of cancer, the major isoform of p63 detected in SCC is also Np63 21, 22, 23, 24, 25. Np63 functions as a transcriptional regulator of different gene subsets 13, 26, 27. Forced expression of Np63 was sufficient to drive proliferation and tumorigenesis 24, while inducible genetic deletion of blocked chemical\induced SCC formation 23, underscoring Np63 as an oncogenic transcription factor in SCCs. Even though role of Np63 has been established, the process controlling Np63 nuclear transport remains poorly comprehended. The nuclear pore complex (NPC) is the single gateway between the nucleus and the cytoplasm 28, 29, 30, 31, 32, 33. NPCs consist of multiple copies of roughly 30 different proteins known as nucleoporins (NUPs). About one\third of NUPs, including NUP62, contain unstructured phenylalanineCglycine (FG) repeats, which form a soft and flexible cobweb composed of ~200 intrinsically disordered polypeptide chains, mediating selective nucleocytoplasmic transport 34, 35. Recently, new evidence suggests that NPC composition varies among different cell types and tissues, and this heterogeneity is required for distinct biological processes such as muscle development, neurogenesis, and embryonic stem cell pluripotency 36, 37, 38, 39, 40, 41. Importantly, single NUP mutation resulted in developmental defects and diseases 42, highlighting the significant role of NUPs in maintaining tissue homeostasis. However, whether and how NUPs are involved in the biology of stratified squamous epithelia GS-9451 remains largely unknown. Here, we demonstrate that this expression of NUP62, one of FG\NUPs, is usually abundant in stratified epithelia. Aberrant overexpression of NUP62 is usually evident in human SCCs. NUP62 expression is required to maintain undifferentiated status of SCCs through regulating Np63 nuclear transport. Mechanistically, pro\differentiation ROCK kinase negatively regulates this Np63 nuclear GS-9451 transport by limiting the conversation between Np63 and NUP62 through phosphorylation of the FG regions GS-9451 of NUP62. Results Identification of NUP62 as a novel differentiation\preventing factor in SCC To explore the expression profile of NUPs in healthy human tissues, we re\analyzed RNA\seq data from your Human Protein Atlas (observe Materials and Methods). The transcript levels of six NUPs (NUP107, NUP85, NUP62, NUP54, NUP188, and TPR) were higher in representative stratified epithelia, skin, and esophagus relative to other NUPs (Fig ?(Fig1A).1A). Among them, NUP62 was the only gene displaying increased expression GS-9451 during induction of the epidermal lineage (Fig ?(Fig1B).1B). To examine expression profile of NUP62 in skin tissue, we performed GS-9451 immunofluorescent confocal microscopic analysis using healthy human skin sample (Fig ?(Fig1C).1C). We found that NUP62 was expressed in the undifferentiated layer, indicating NUP62 is usually expressed in the progenitor populace. Open in a separate.