Study on the regulatory mechanism of EAF2 in the microenvironment of cervical cancer

Objective EAF2 plays an important role in transcription elongation and the regulation of gene expression in mammalian cells. EAF2’s depletion has been demonstrated to enhance cell proliferation and greatly increase the risk of cancer. Even so, its expression and prognostic role in cervical cancer (CC) remains controversial. Methods To solve this issue, we comprehensively investigated the role of EAF2 in CC through various databases including ONCOMINE, UALCAN, Kaplan-Meier Plotter and TIMER. Results In all, we found that the EAF2 was highly expressed in CC tissue and was significantly correlated with better patient survival. Among the CNAs, amplification was the dominant alteration. Then the co-expression profile and enrichment analysis of EAF2 were related to the potential signaling pathways. The function of genes such as Kinase LYN, mi-RNA133A-133B and transcription factor OCT1 were also enriched in CC. The positively relation EAF2 expression to 6 immune cells revealed that EAF2 expression may affect development of patients with CC partially due to immune infiltration. Conclusions Taken together, our data suggest that EAF2 might be a potential prognostic marker and therapeutic target for CC patients.

Physiologically relevant miRNAs in mammalian oocytes are rare and highly abundant.

miRNAs, ~22nt small RNAs associated with Argonaute (AGO) proteins, are important negative regulators of gene expression in mammalian cells. However, mammalian maternal miRNAs show negligible repressive activity and the miRNA pathway is dispensable for oocytes and maternal-to-zygotic transition. The stoichiometric hypothesis proposed that this is caused by dilution of maternal miRNAs during oocyte growth. As the dilution affects miRNAs but not mRNAs, it creates unfavorable miRNA:mRNA stoichiometry for efficient repression of cognate mRNAs. Here we report that porcine ssc-miR-205 and bovine bta-miR-10b are exceptional miRNAs, which resist the diluting effect of oocyte growth and can efficiently suppress gene expression. Additional analysis of ssc-miR-205 shows that it has higher stability, reduces expression of endogenous targets, and contributes to porcine oocyte-to-embryo transition. Consistent with the stoichiometric hypothesis, our results show that the endogenous miRNA pathway in mammalian oocytes is intact and that maternal miRNAs can efficiently suppress gene expression when a favorable miRNA:mRNA stoichiometry is established.

First person – Kazuko Okamoto

ABSTRACT First Person is a series of interviews with the first authors of a selection of papers published in Biology Open, helping early-career researchers promote themselves alongside their papers. Kazuko Okamoto is first author on ‘ Pressure-induced changes on the morphology and gene expression in mammalian cells’, published in BiO. Kazuko conducted the research described in this article while a research scientist in Tomonobu M. Watanabe's lab at RIKEN Center for Biosystems Dynamics Research, Kobe, Japan. She is now an assistant professor in the lab of Satoru Okuda at Nano Life Science Institute, Kanazawa University, Japan, investigating intracellular communication and transcription regulation.

Targeting of SET/I2PP2A oncoprotein inhibits Gli1 transcription revealing a new modulator of Hedgehog signaling

The Hedgehog (Hh)/Gli signaling pathway controls cell proliferation and differentiation, is critical for the development of nearly every tissue and organ in vertebrates and is also involved in tumorigenesis. In this study, we characterize the oncoprotein SET/I2PP2A as a novel regulator of Hh signaling. Our previous work has shown that the zebrafish homologs of SET are expressed during early development and localized in the ciliated organs. In the present work, we show that CRISPR/Cas9-mediated knockdown of setb gene in zebrafish embryos resulted in cyclopia, a characteristic patterning defect previously reported in Hh mutants. Consistent with these findings, targeting setb gene using CRISPR/Cas9 or a setb morpholino, reduced Gli1-dependent mCherry expression in the Hedgehog reporter zebrafish line Tg(12xGliBS:mCherry-NLS). Likewise, SET loss of function by means of pharmacological inhibition and gene knockdown prevented the increase of Gli1 expression in mammalian cells in vitro. Conversely, overexpression of SET resulted in an increase of the expression of a Gli-dependent luciferase reporter, an effect likely attributable to the relief of the Sufu-mediated inhibition of Gli1. Collectively, our data support the involvement of SET in Gli1-mediated transcription and suggest the oncoprotein SET/I2PP2A as a new modulator of Hedgehog signaling.

Controlling gene expression in mammalian cells using multiplexed conditional guide RNAs for Cas12a

Spatiotemporal control of the activity of Cas proteins is of considerable interest for both basic research and therapeutics. Only few mechanisms have been demonstrated for regulating the activity of guide RNAs (gRNAs) for Cas12a in mammalian cells, however, and combining and compactly integrating multiple control instances on single transcripts has not been possible so far. Here, we show that conditional processing of the 3’ tail is a viable general approach towards switchable Pol II-transcribed Cas12a gRNAs that can activate gene expression in mammalian cells in an input-dependent manner. Processing of the 3’ tail can be achieved using microRNA and short hairpin RNA as inputs, via a guanine-responsive ribozyme, and also using an RNA strand displacement mechanism. We further show that Cas12a along with several independently switchable gRNAs can be integrated on a single transcript using stabilizing RNA triplexes, providing a route towards compact Cas12a-based gene regulation constructs with multi-input switching capabilities.

Interaction between zinc, GPR39, BDNF and neuropeptides in depression

: As one of the most important elements in our body, zinc plays a part in both the pathophysiology of depression and the antidepressant response. Patients suffering from major depression show significantly reduced zinc levels, which are normalized following successful antidepressant treatment. Recent studies have shown the interaction between zinc, GPR39 and neuropeptides, including galanin and neuropeptide Y (NPY). The zinc-sensing receptor GPR39 forms heterotrimers with 5-HT1A and the galanin receptor GalR1 upon their co-expression in mammalian cells. The oligomerization of these heterotrimers is regulated by the zinc concentration, and this may have an influence on depressive-like behavior. The antidepressant-like effect of zinc is linked to elevated levels of brain-derived neurotrophic factor (BDNF) in brain structures associated with emotion, such as the hippocampus and the amygdala. BDNF regulates neuropeptides, including NPY, cholecystokinin (CCK), and substance P or galanin, which are also implicated in mood disorders. This review focuses for the first time on the interaction between zinc, the GPR39 zinc receptor, BDNF and selected neuropeptides in terms of depression in order to determine its possible role in the neuropharmacology of that illness.