We reveal by high‐throughput screening that activating transcription factor 1 (ATF1) is a novel pluripotent regulator in human embryonic stem cells (hESCs). The knockdown of ATF1 expression significantly up‐regulated neuroectoderm (NE) genes but not mesoderm, endoderm, and trophectoderm genes. Of note, down‐regulation or knockout of ATF1 with short hairpin RNA (shRNA), small interfering RNA (siRNA), or clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR‐associated protein 9 (Cas9) was sufficient to up‐regulate sex‐determining region Y‐box (SOX)2 and paired box 6 (PAX6) expression under the undifferentiated or differentiated conditions, whereas overexpression of ATF1 suppressed NE differentiation. Endogenous ATF1 was spontaneously down‐regulated after d 1–3 of neural induction. By double‐knockdown experiments, up‐regulation of SOX2 was critical for the increase of PAX6 and SOX1 expression in shRNA targeting Atf1 hESCs. Using the luciferase reporter assay, we identified ATF1 as a negative transcriptional regulator of Sox2 gene expression. A novel function of ATF1 was discovered, and these findings contribute to a broader understanding of the very first steps in regulating NE differentiation in hESCs.—Yang, S.‐C, Liu, J.‐J., Wang, C.‐K., Lin, Y.‐T., Tsai, S.‐Y., Chen, W.‐J., Huang, W.‐K., Tu, P.‐W. A., Lin, Y.‐C, Chang, C.‐F., Cheng, C.‐L., Lin, H., Lai, C.‐Y., Lin, C.‐Y., Lee, Y.‐H., Chiu, Y.‐C., Hsu, C.‐C., Hsu, S.‐C., Hsiao, M., Schuyler, S. C., Lu, F. L., Lu, J. Down‐regulation of ATF1 leads to early neuroectoderm differentiation of human embryonic stem cells by increasing the expression level of SOX2. FASEB J. 33, 10577–10592 (2019). http://www.fasebj.org

The developmental potential within pluripotent cells in the canonical model is restricted to embryonic tissues, whereas totipotent cells can differentiate into both embryonic and extraembryonic tissues. Currently, the ability to culture in vitro totipotent cells possessing molecular and functional features like those of an early embryo in vivo has been a challenge. Recently, it was reported that treatment with a single spliceosome inhibitor, pladienolide B (plaB), can successfully reprogram mouse pluripotent stem cells into totipotent blastomere-like cells (TBLCs) in vitro. The TBLCs exhibited totipotency transcriptionally and acquired expanded developmental potential with the ability to yield various embryonic and extraembryonic tissues that may be employed as novel mouse developmental cell models. However, it is disputed whether TBLCs are ‘true’ totipotent stem cells equivalent to in vivo two-cell stage embryos. To address this question, single-cell RNA sequencing was applied to TBLCs and cells from early mouse embryonic developmental stages and the data were integrated using canonical correlation analyses. Differential expression analyses were performed between TBLCs and multi-embryonic cell stages to identify differentially expressed genes. Remarkably, a subpopulation within the TBLCs population expressed a high level of the totipotent-related genes Zscan4s and displayed transcriptomic features similar to mouse two-cell stage embryonic cells. This study underscores the subtle differences between in vitro derived TBLCs and in vivo mouse early developmental cell stages at the single-cell transcriptomic level. Our study has identified a new experimental model for stem cell biology, namely ‘cluster 3’, as a subpopulation of TBLCs that can be molecularly defined as near totipotent cells.

Deciphering signaling mechanisms critical for the extended pluripotent stem cell (EPSC) state and primed pluripotency is necessary for understanding embryonic development. Here, a membrane protein, podocalyxin-like protein 1 (PODXL) as being essential for extended and primed pluripotency, is identified. Alteration of PODXL expression levels affects self-renewal, protein expression of c-MYC and telomerase, and induced pluripotent stem cell (iPSC) and EPSC colony formation. PODXL is the first membrane protein reported to regulate de novo cholesterol biosynthesis, and human pluripotent stem cells (hPSCs) are more sensitive to cholesterol depletion than fibroblasts. The addition of exogenous cholesterol fully restores PODXL knockdown-mediated loss of pluripotency. PODXL affects lipid raft dynamics via the regulation of cholesterol. PODXL recruits the RAC1/CDC42/actin network to regulate SREBP1 and SREBP2 maturation and lipid raft dynamics. Single-cell RNA sequencing reveals PODXL overexpression enhanced chimerism between human cells in mouse host embryos (hEPSCs 57%). Interestingly, in the human-mouse chimeras, laminin and collagen signaling-related pathways are dominant in PODXL overexpressing cells. It is concluded that cholesterol regulation via PODXL signaling is critical for ESC/EPSC.

ILAR routing protocol was proposed to improve the efficiency of location-aided routing (LAR) protocol. It had less packets and better performance than LAR. However, ILAR still can be improved on hop counts for speed up routing discovery. We found two drawbacks that in the ILAR. There are some nodes around the borders of broadcasts coverage could move out easily, it lead to routing path broken. Another problem in the ILAR protocol was choosing the next forwarding node based on VDIST distance, but it can't choose better node causes far node's VDIST greater than forwarding node. Therefore we propose a High-effect Location-Aided Routing protocol (HLAR) and it solves the problems above. The simulation results our scheme has better performance than ILAR scheme.

In the postpandemic era, wearing protective masks in public places will still be an important means of blocking popular viruses in the future. (1) Background: The purpose of this study was to explore whether sports performance was affected by mask wearing and exercise duration during 15-minute treadmill running at a speed of 75% maximal aerobic speed. (2) Methods: Thirty-six males were randomly divided into mask and nonmask groups. The kinematic and kinetic data were obtained at four time points (RN0-1 min, RN5-6 min, RN9-10 min, and RN14-15 min) after running. Two-way repeated-measures ANOVA was applied to examine the effects between groups and times with Bonferroni post hoc comparison. (3) Results: The results showed that there was no difference between mask and nonmask group during running (p > 0.05). As running time increased, hip joint ROM, hip joint flexion/extension max, and ankle joint plantarflexion max angles increased; knee joint flexion min and ankle joint dorsiflexion max angles decreased; average peak vertical ground reaction forces (PVGRF) increased after 9 min-running (p < 0.05). (4) Conclusions: Wearing a medical protective mask does not affect the joint angle and touchdown PVGRF of lower extremities during treadmill running while affected by running time and changed after 9 min-treadmill running. Future studies will examine the effects of wearing masks during the pandemic on muscle activation and blood biochemical values during exercise. The trial was registered prospectively with trial registration number (TRN) of ChiCTR2000040535 and date of registration in December 1, 2020.