Small open reading frames (sORFs) are often overlooked features in genomes. In the past, they were labeled as noncoding or “transcriptional noise”. However, accumulating evidence from recent years suggests that sORFs may be transcribed and translated to produce sORF-encoded polypeptides (SEPs) with less than 100 amino acids. The vigorous development of computational algorithms, ribosome profiling, and peptidome has facilitated the prediction and identification of many new SEPs. These SEPs were revealed to be involved in a wide range of basic biological processes, such as gene expression regulation, embryonic development, cellular metabolism, inflammation, and even carcinogenesis. To effectively understand the potential biological functions of SEPs, we discuss the history and development of the newly emerging research on sORFs and SEPs. In particular, we review a range of recently discovered bioinformatics tools for identifying, predicting, and validating SEPs as well as a variety of biochemical experiments for characterizing SEP functions. Lastly, this review underlines the challenges and future directions in identifying and validating sORFs and their encoded micropeptides, providing a significant reference for upcoming research on sORF-encoded peptides.

Spider venom has been found to show its anticancer activity in a variety of human malignancies, including lung cancer. In this study, we investigated the anti-cancer peptide toxin LVTX-8, with linear amphipathic alpha-helical conformation, designed and synthesized from the cDNA library of spider Lycosa vittata. Multiple cellular methods, such as CCK-8 assay, flow cytometry, colony formation assay, Transwell invasion and migration assay, were performed to detect peptide-induced cell growth inhibition and anti-metastasis in lung cancer cells. Our results demonstrated that LVTX-8 displayed strong cytotoxicity and anti-metastasis towards lung cancer in vitro. Furthermore, LVTX-8 could suppress the growth and metastasis of lung cancer cells (A549 and H460) in nude mouse models. Transcriptomics, integrated with multiple bioinformatics analysis, suggested that the molecular basis of the LVTX-8-mediated inhibition of cancer cell growth and metastasis manifested in two aspects: Firstly, it could restrain the activity of cancer cell division and migration through the functional pathways, including “p53 hypoxia pathway” and “integrin signaling”. Secondly, it could regulate the expression level of apoptotic-related proteins, which may account for programmed apoptosis of cancer cells. Taken together, as an anticancer peptide with high efficiency and acceptable specificity, LVTX-8 may become a potential precursor of a therapeutic agent for lung cancer in the future.

Background: Activity-dependent neuroprotective protein (ADNP), which is involved in embryonic development and neurogenesis, has been proven to be upregulated in some human tumors. However, its role in bladder cancer (BC) has never been studied. Objective: We aimed to investigate the mechanisms by which ADNP promotes the progression of BC. Methods: ADNP expressions in BC cell lines and paired BC and adjacent normal tissues were measured by quantitative real-time PCR (qRT-PCR), Western blot, and immunohistochemistry. Colony formation, Cell Counting Kit-8 (CCK-8), trypan blue exclusion assay, flow cytometry, and nude mice tumorigenesis assay were performed to explore the effects of ADNP on growth of BC in vivo and in vitro. The impacts of ADNP on AKT signaling pathways were measured by Western blot. Results: The expression of ADNP mRNA and protein was significantly upregulated in BC tissues compared with adjacent normal tissues. Immunohistochemical analysis of 221 BC and 51 adjacent normal tissue paraffin sections indicated that ADNP expression was significantly associated with histological classification and pathological T and N stages. Survival analysis revealed that patients with high ADNP expression have worse prognosis with respect to overall survival and progression-free disease. ADNP knockdown markedly delayed propagation of BC in vitro and the development of BC in vivo. ADNP overexpression showed the opposite effect. In addition, ADNP can markedly promote G1-S cell cycle transition in BC cells. On the molecular level, we confirmed that ADNP mediated acceleration of G1-S transition was associated with activation of the AKT pathways in BC. Conclusion: ADNP is overexpressed in BC and promotes BC growth partly through AKT pathways. ADNP is crucial in predicting the outcome of BC patients and may be a potential therapeutic target in BC.

Introduction: The pathogenic gene CDH23 plays a pivotal role in tip links, which is indispensable for mechanoelectrical transduction in the hair cells. However, the underlying molecular mechanism and signal regulatory networks that influence deafness is still largely unknown.Methods: In this study, a congenital deafness family, whole exome sequencing revealed a new mutation in the pathogenic gene CDH23, subsequently; the mutation has been validated using Sanger sequencing method. Then CRISPR/Cas9 technology was employed to knockout zebrafish cdh23 gene. Startle response experiment was used to compare with wide-type, the response to sound stimulation between wide-type and cdh23^−/−. To further illustrate the molecular mechanisms underlying congenital deafness, comparative transcriptomic profiling and multiple bioinformatics analyses were performed.Results: The YO-PRO-1 assay result showed that in cdh23 deficient embryos, the YO-PRO-1 signal in inner ear and lateral line neuromast hair cells were completely lost. Startle response experiment showed that compared with wide-type, the response to sound stimulation decreased significantly in cdh23 mutant larvae. Comparative transcriptomic showed that the candidate genes such as atp1b2b and myof could affect hearing by regulating ATP production and purine metabolism in a synergetic way with cdh23. RT-qPCR results further confirmed the transcriptomics results. Further compensatory experiment showed that ATP treated cdh23^−/− embryos can partially recover the mutant phenotype.Conclusion: In conclusion, our study may shed light on deciphering the principal mechanism and provide a potential therapeutic method for congenital hearing loss under the condition of CDH23 mutation.