The CRHR1/CREB/REST signaling cascade regulates mammalian embryonic neural stem cell properties

Joint-tissue integrative analysis identifies high-risk genes for Parkinson's disease

The loss of dopaminergic neurons in the substantia nigra and the abnormal accumulation of synuclein proteins and neurotransmitters in Lewy bodies constitute the primary symptoms of Parkinson's disease (PD). Besides environmental factors, scholars are in the early stages of comprehending the genetic factors involved in the pathogenic mechanism of PD. Although genome-wide association studies (GWAS) have unveiled numerous genetic variants associated with PD, precisely pinpointing the causal variants remains challenging due to strong linkage disequilibrium (LD) among them. Addressing this issue, expression quantitative trait locus (eQTL) cohorts were employed in a transcriptome-wide association study (TWAS) to infer the genetic correlation between gene expression and a particular trait. Utilizing the TWAS theory alongside the enhanced Joint-Tissue Imputation (JTI) technique and Mendelian Randomization (MR) framework (MR-JTI), we identified a total of 159 PD-associated genes by amalgamating LD score, GTEx eQTL data, and GWAS summary statistic data from a substantial cohort. Subsequently, Fisher's exact test was conducted on these PD-associated genes using 5,152 differentially expressed genes sourced from 12 PD-related datasets. Ultimately, 29 highly credible PD-associated genes, including CTX1B, SCNA, and ARSA, were uncovered. Furthermore, GO and KEGG enrichment analyses indicated that these genes primarily function in tissue synthesis, regulation of neuron projection development, vesicle organization and transportation, and lysosomal impact. The potential PD-associated genes identified in this study not only offer fresh insights into the disease's pathophysiology but also suggest potential biomarkers for early disease detection.

Single-Cell Transcriptome Analysis Reveals Development-Specific Networks at Distinct Synchronized Antral Follicle Sizes in Sheep Oocytes

The development of the ovarian antral follicle is a complex, highly regulated process. Oocytes orchestrate and coordinate the development of mammalian ovarian follicles, and the rate of follicular development is governed by a developmental program intrinsic to the oocyte. Characterizing oocyte signatures during this dynamic process is critical for understanding oocyte maturation and follicular development. Although the transcriptional signature of sheep oocytes matured in vitro and preovulatory oocytes have been previously described, the transcriptional changes of oocytes in antral follicles have not. Here, we used single-cell transcriptomics (SmartSeq2) to characterize sheep oocytes from small, medium, and large antral follicles. We characterized the transcriptomic landscape of sheep oocytes during antral follicle development, identifying unique features in the transcriptional atlas, stage-specific molecular signatures, oocyte-secreted factors, and transcription factor networks. Notably, we identified the specific expression of 222 genes in the LO, 8 and 6 genes that were stage-specific in the MO and SO, respectively. We also elucidated signaling pathways in each antral follicle size that may reflect oocyte quality and in vitro maturation competency. Additionally, we discovered key biological processes that drive the transition from small to large antral follicles, revealing hub genes involved in follicle recruitment and selection. Thus, our work provides a comprehensive characterization of the single-oocyte transcriptome, filling a gap in the mapping of the molecular landscape of sheep oogenesis. We also provide key insights into the transcriptional regulation of the critical sizes of antral follicular development, which is essential for understanding how the oocyte orchestrates follicular development.

Corticotropin-Releasing Hormone: A Novel Stimulator of Somatolactin in Teleost Pituitary Cells

Corticotropin-releasing hormone (CRH) is known for its crucial role in the stress response system, which could induce pituitary adrenocorticotropic hormone (ACTH) secretion to promote glucocorticoid release in the adrenal gland. However, little is known about other pituitary actions of CRH in teleosts. Somatolactin is a fish-specific hormone released from the neurointermediate lobe (NIL) of the posterior pituitary. A previous study has reported that ACTH was also located in the pituitary NIL region. Interestingly, our present study found that CRH could significantly induce two somatolactin isoforms' (SLα and SLβ) secretion and synthesis in primary cultured grass carp pituitary cells. Pharmacological analysis further demonstrated that CRH-induced pituitary somatolactin expression was mediated by the AC/cAMP/PKA, PLC/IP3/PKC, and Ca2+/CaM/CaMK-II pathways. Finally, transcriptomic analysis showed that both SLα and SLβ should play an important role in the regulation of lipid metabolism in primary cultured hepatocytes. These results indicate that CRH is a novel stimulator of somatolactins in teleost pituitary cells, and somatolactins may participate in the stress response by regulating energy metabolism.

REST in the Road Map of Brain Development

Repressor element-1 silencing transcription factor (REST) or also known as neuron-restrictive silencing factor (NRSF), is the key initiator of epigenetic neuronal gene-expression modification. Identification of a massive number of REST-targeted genes in the brain signifies its broad involvement in maintaining the functionality of the nervous system. Additionally, REST plays a crucial role in conferring neuroprotection to the neurons against various stressors or insults during injuries. At the cellular level, nuclear localisation of REST is a key determinant for the functional transcriptional regulation of REST towards its target genes. Emerging studies reveal the implication of REST nuclear mislocalisation or dysregulation in several neurological diseases. The expression of REST varies depending on different types of neurological disorders, which has created challenges in the discovery of REST-targeted interventions. Hence, this review presents a comprehensive summary on the physiological roles of REST throughout brain development and its implications in neurodegenerative and neurodevelopmental disorders, brain tumours and cerebrovascular diseases. This review offers valuable insights to the development of potential therapeutic approaches targeting REST to improve pathologies in the brain. The important roles of REST as a key player in the nervous system development, and its implications in several neurological diseases.

STAC1 is required for glioblastoma cell invasion and survival

Glioblastoma Multiforme (GBM) is a highly malignant brain tumor with poor prognosis. Understanding the molecular mechanisms driving GBM tumorigenesis is crucial for developing effective therapeutic strategies. This study investigates the role of STAC1, a gene belonging to the SH3 and cysteine-rich domain family, in glioblastoma cell invasion and survival. Computational analyses of patient samples reveal that STAC1 expression is elevated in GBM tissues, and higher STAC1 expression is associated with lower overall survival rates. Consistently, we find that overexpression of STAC1 in glioblastoma cells enhances invasion, while knockdown of STAC1 reduces invasion and the expression of genes associated with epithelial-to-mesenchymal transition (EMT). STAC1 depletion also induces apoptosis in glioblastoma cells. Furthermore, we show that STAC1 regulates AKT and calcium channel signaling in glioblastoma cells. Collectively, our study provides valuable insights into the pathogenic roles of STAC1 in GBM and highlights its potential as a promising target for the treatment of high-grade glioblastoma.