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Biology subjects

Lian, X.

Publications and source records attributed to Lian, X..

5 recordsLinked to original sources

Transfer learning via multi-scale convolutional neural layers for human-virus protein-protein interaction prediction

To predict interactions between human and viral proteins, we combine evolutionary sequence profile features with a Siamese convolutional neural network (CNN) architecture and a multi-layer perceptron (MLP). Our architecture outperforms various feature encodings-based machine learning and state-of-the-art prediction methods. As our main contribution, we introduce two types of transfer learning methods (i.e., frozen type and fine-tuning type) that reliably predict interactions in a target human-virus domain based on training in a source human-virus domain, by retraining CNN layers. Our transfer learning strategies can effectively apply prior knowledge transfer from large source dataset/task to small target dataset/task to improve prediction performance. Finally, we utilize the frozen type of transfer learning to predict human-SARS-CoV-2 PPIs, indicating that our predictions are topologically and functionally similar to experimentally known interactions. Source code and datasets are available at https://github.com/XiaodiYangCAU/TransPPI/.

bioinformatics

Activation of central 5HT2A receptor in brain inhibited the seizure-induced respiratory arrest in the DBA/1 mouse SUDEP model

Sudden unexpected death in epilepsy (SUDEP) is the leading cause of death among epilepsy patients, occurring even more frequently in cases with anti-epileptic drug resistance. However, the underlying mechanism of SUDEP remains elusive. Our previous study demonstrated that enhancement of serotonin (5-HT) synthesis by intraperitoneal (IP) injection of 5-hydroxytryptophan (5-HTP) significantly reduced the incidence of seizure-induced respiratory arrest (S-IRA) in a DBA/1 mouse SUDEP model. Given that the 5-HT2A receptor (5-HT2AR) plays an important role in mediating the respiration system in the brain, we hypothesized that 5-HT2AR plays a key role in S-IRA and SUDEP. To test this hypothesis, we examined whether the decreased incidence of S-IRA evoked by either acoustic stimulation or pentylenetetrazole (PTZ) injection following 5-HTP administration will be blocked by treatment with ketanserin (KET), a selective antagonist of 5HT2AR, in the DBA/1 mouse SUDEP model. We observed that the reduction in S-IRA by 5-HTP was significantly reversed by IP or intracerebroventricular injection of KET. Considering the localization of 5-HT2AR in the pre-Botzinger complex (PBC), which plays a key role in regulating respiratory rhythm, we next examined whether KET acts on 5-HT2AR in the PBC. To test this hypothesis, we activated the neural circuit between the dorsal raphe nucleus (DR) and PBC using optogenetics technology. We observed that stimulation of TPH2-ChETA-expressing neurons in the DR reduced the incidence of S-IRA evoked by PTZ, and this suppressant effect was significantly reversed by administration of KET in the bilateral PBC with no changes in electroencephalogram activity. The neural circuit between the DR and PBC was confirmed by injection of cholera toxin subunit B555 (CTB-555), a nerve tracer, in the DR or PBC separately. Calcium signaling evoked by PTZ within neurons of the PBC during seizures was significantly reduced by photostimulation of the DR. Taken together, our findings suggest that 5-HT2AR plays a critical role in regulating S-IRA and targeting the serotonergic neural circuit between the DR and PBC is a promising approach to preventing SUDEP.

neuroscience

Genome-wide association study of flowering time reveals complex genetic heterogeneity and epistatic interactions in rice

Since domestication, rice has cultivated in a wide range of latitudes with different day lengths. Selection of diverse natural variations in heading date and photoperiod sensitivity is critical for adaptation of rice to different geographical environments. To unravel the genetic architecture underlying natural variation of rice flowering time, we conducted a genome wide association study (GWAS) using several association analysis strategies with a diverse worldwide collection of 529 O. sativa accessions. Heading date was investigated in three environments under long-day or short-day conditions, and photosensitivity was evaluated. By dividing the whole association panel into subpopulations and performing GWAS with both linear mixed models and multi-locus mixed-models, we revealed hundreds of significant loci harboring novel candidate genes as well as most of the known flowering time genes. In total, 127 hotspots were detected in at least two GWAS. Universal genetic heterogeneity was found across subpopulations. We further detected abundant interactions between GWAS loci, especially in indica. Functional gene families were revealed from enrichment analysis of the 127 hotspots. The results demonstrated a rich of genetic interactions in rice flowering time genes and such epistatic interactions contributed to the large portions of missing heritability in GWAS. It suggests the increased complexity of genetic heterogeneity might discount the power of increasing the sample sizes in GWAS.

genetics

Efficacy of transoral laser surgery versus linear accelerator radiotherapy for the treatment of T1 glottic carcinoma: a meta-analysis of oncologic outcomes

ObjectiveA meta-analysis was conducted to compare oncologic outcomes for patients of T1 glottic carcinoma who were treated with transoral laser surgery (TLS) or linear accelerator radiotherapy (linac RT). MethodsAll related studies published up to September 2019 were acquired by searching Pubmed, EMBASE, and Cochrane, with the index words: glottic, vocal, laryngeal, radiation, radiotherapy, irradiation, laser, surgery, cordectomy, carcinoma and cancer. Relative studies which compared oncologic outcomes between linac RT and TLS were included. Sensitivity analysis were performed to evaluate heterogeneity. ResultsA total of twelve eligible studies were included for the analysis, which contained three prospective studies and nine retrospective studies. Patients who underwent TLS had increased overall survival (OR = 1.40, 95% CI=1.02-1.94, P=0.04) and laryngeal preservation (OR = 5.37, 95% CI = 3.05-9.44, P < 0.00001) versus who underwent linac RT. No statistical difference was observed between TLS group and linac RT group in terms of local control (OR=0.88, 95% CI = 0.62-1.24, P = 0.47), disease-specific survival (OR = 0.61, 95% CI = 0.26-1.43, P = 0.26), and disease-free survival (OR = 1.63, 95% CI = 0.70-3.81, P = 0.14). ConclusionsThe results of this meta-analysis indicate that there were clinical benefits for patients with glottic carcinoma after TLS compared with linac RT with respect to overall survival and laryngeal preservation. However, more multi-center randomized controlled trials would be urgently needed to prove these differences.

cancer biology

Sulfopin, a selective covalent inhibitor of Pin1, blocks Myc-driven tumor initiation and growth in vivo

The peptidyl-prolyl cis-trans isomerase, Pin1, acts as a unified signaling hub that is exploited in cancer to activate oncogenes and inactivate tumor suppressors, in particular through up-regulation of c-Myc target genes. However, despite considerable efforts, Pin1 has remained an elusive drug target. Here, we screened an electrophilic fragment library to discover covalent inhibitors targeting Pin1s active site nucleophile - Cys113, leading to the development of Sulfopin, a double-digit nanomolar Pin1 inhibitor. Sulfopin is highly selective for Pin1, as validated by two independent chemoproteomics methods, achieves potent cellular and in vivo target engagement, and phenocopies genetic knockout of Pin1. Although Pin1 inhibition had a modest effect on viability in cancer cell cultures, Sulfopin induced downregulation of c-Myc target genes and reduced tumor initiation and tumor progression in murine and zebrafish models of MYCN-driven neuroblastoma. Our results suggest that Sulfopin is a suitable chemical probe for assessing Pin1-dependent pharmacology in cells and in vivo. Moreover, these studies indicate that Pin1 should be further investigated as a potential cancer target.

cancer biology