Project description:Lysine lactylation, a new post-translational modification identified on histones of human and mouse cells, stimulates gene transcription from chromatin directly. However, very little is known in the scope and cellular distribution of lactylated proteins. In the present study, we conducted the first proteome-wide survey of lactylated sites in Trypanosoma brucei, a unicellular parasite causing human African sleeping sickness and livestock nagana disease, using LC-MS/MS to identify peptides enriched by immuno-purification with an anti-lactyllysine antibody. Overall, we identified 387 unique lysine lactylated sites in 257 lactylated proteins with diverse cellular localizations and biological functions. Lactylated proteins are involved in a wide variety of cellular functions such as metabolism and gene regulation. Further, we demonstrate that the lactate-derived lactylation in trypanosome is regulated by glucose metabolism. Collectively, our findings provide the first comprehensive view of the lactylome of T. brucei and suggest that lysine lactylation in trypanosomes involves a diverse array of cellular functions.
Project description:To gain a more complete understanding of how porcine cathelicidin PR-39 influence the porcine intestinal epithelial cells, we profiled gene expression patterns in IPEC-J2 cell line in the presence or the absence of PR-39.
Project description:Lysine lactylation (Kla) is a new posttranslational modification (PTM) identified in histone and nonhistone proteins of several eukaryotic cells that directly activate gene expression and DNA replication. However, very little is known about their scope and cellular distribution in apicomplexan parasites that are important to public and animal health. Toxoplasma gondii, the agent of toxoplasmosis, is one of obligate intracellular apicomplexan parasite that can infect all kinds of nucleated cells of animals and humans. Using this parasite as model organism, herein, we produced the first global lysine lactylome profile through LC-MS/MS. Overall, a total of 983 Kla sites occurred on 523 lactylated proteins were identified in Toxoplasma tachyzoites, the acute toxoplasmosis-causing stage. Bioinformatics analysis revealed that these lactylated proteins are evolutionarily conserved and involved in a wide variety of cellular functions such as energy metabolism, gene regulation and protein biosynthesis. Moreover, the results from subcellular localization analysis and IFA showed that the majority of lactylated T. gondii proteins localized in the nucleus, indicating a potential impact of Kla on gene regulation. Notably, an extensive batch of parasite-specific proteins unique to Apicomplexa is lactylated in T. gondii. Our findings revealed that Kla was widespread in the early branching eukaryotic cell, and that lactylated proteins, including a crowd of unique parasite proteins, were involved in a remarkably diverse array of cellular functions. These valuable data will improve our understanding of the evolution of Kla while potentially providing novel therapeutic avenues.
Project description:<p>Interstitial renal inflammation contributes to the transition from acute kidney injury (AKI) to chronic kidney disease (CKD). Recently, protein lactylation modification has emerged as a novel mechanism for mediating chronic organ damage. We investigated lactylated protein profiles and the role of protein lactylation during AKI progression. Severe and moderate AKI mouse models were constructed by bilateral renal ischemia for 35 and 25 min, respectively. Lactylation enhancers and inhibitors were used to verify the effect of protein lactylation. Lactylated proteomics was used to detect lactylated protein changes in kidneys, and the lactylated proteins related to kidney injury were screened for verification. We observed significantly higher lactate and protein lactylation levels in the severe AKI model than in the moderate AKI model 1-28 days post-injury. Inhibition of protein lactylation protects against renal interstitial fibrosis. In vitro and in vivo experiments demonstrated that protein lactylation activated Nod-like receptor protein 3 (NLRP3) inflammasomes, promoting the AKI-CKD transition. Comprehensive lactylome profiling of severe AKI models revealed a role for lactylated proteins in metabolic pathways, primarily the tricarboxylic acid (TCA) cycle, where the rate-limiting enzyme, citrate synthase (CS), exhibited significantly elevated lactylation levels 3-7 days post-AKI induction; K370 was the most significant lysine residue. In vitro, following hypoxia/reoxygenation, the modified/lactylated K370T group significantly decreased CS activity and mitochondrial function. Furthermore, CS-K370 lactylation activated the NLRP3 inflammasomes. Thus, lactylation of CS promotes the AKI-CKD transition through NLRP3 inflammasome activation. Inhibition of CS lactylation shows therapeutic potential for preventing this transition.</p>
Project description:Using two complementary approaches, analysis of imprinting of candidate genes by pyrosequencing and expression profiling of parthenogenetic fetuses, we carried a comprehensive survey of genomic imprinting in swine. In the case of imprinted genes where transcription of one of the two parental alleles is silenced, uniparental embryos like parthenotes can be used to measure transcript dosage effects. Using Affymetrix Porcine GeneChip microarrays, four tissues of day 30 fetuses were profiled: brain, fibroblast, liver, and placenta. Keywords: Transcriptional profiling of epigenetic asymmetry in porcine day 30 parthenogenetic and biparental fetal tissues
Project description:Embryonic stem cells (ESCs) favor glycolysis over oxidative phosphorylation for energy production, and glycolytic metabolism is critical for pluripotency establishment, maintenance and exit. However, how glycolysis regulates the self-renewal and differentiation of ESCs remains elusive. Here, we demonstrated that protein lactylation, regulated by intracellular lactate, contributes to the self-renewal of ESCs. Next, the lactylome profiles of ESCs with and without a lactate dehydrogenase (Ldh) inhibitor, which suppresses the conversion of pyruvate to lactate, were depicted. It was notable that many lactylated proteins are involved in the self-renewal and differentiation of ESCs. We further showed that Esrrb, an orphan nuclear receptor involved in pluripotency maintenance and extraembryonic endoderm stem cell (XEN) differentiation, is lactylated on K228 and K232. Lactylation of Esrrb enhances its activity in promoting ESC self-renewal in the absence of LIF and XEN differentiation of ESCs, through increasing its binding at target genes. Our studies reveal the importance of protein lactation in the self-renewal and XEN differentiation of ESCs, and the underlying mechanism for glycolytic metabolism regulating cell fate choice.