Gene: X最新文献

Post-fermentation fungal biomass waste provides a viable source for chitin. Cell wall chitin of filamentous fungi, and in particular its de-N-acetylated derivative chitosan, has a wide range of commercial applications. Although the cell wall of filamentous fungi comprises 10-30% chitin, these yields are too low for cost-effective production. Therefore, we aimed to identify the genes involved in increased chitin deposition by screening a collection of UV-derived cell wall mutants in Aspergillus niger. This screen revealed a mutant strain (RD15.4#55) that showed a 30-40% increase in cell wall chitin compared to the wild type. In addition to the cell wall chitin phenotype, this strain also exhibited sensitivity to SDS and produces an unknown yellow pigment. Genome sequencing combined with classical genetic linkage analysis identified two mutated genes on chromosome VII that were linked with the mutant phenotype. Single gene knockouts and subsequent complementation analysis revealed that an 8 bp deletion in NRRL3_09595 is solely responsible for the associated phenotypes of RD15.4#55. The mutated gene, which was named cwcA (cell wall chitin A), encodes an orthologue of Saccharomyces cerevisiae Bypass of ESS1 (BYE1), a negative regulator of transcription elongation. We propose that this conserved fungal protein is involved in preventing cell wall integrity signaling under non-inducing conditions, where loss of function results in constitutive activation of the cell wall stress response pathway, and consequently leads to increased chitin content in the mutant cell wall.

Amidst technical challenges which limit successful culture and genetic manipulation of P. vivax parasites, we used a computational approach to identify a critical target with evolutionary significance. The putative circumsporozoite protein on chromosome 13 of P. vivax (PvpuCSP)is distinct from the well-known vaccine candidate PfCSP. The aim of this study was to understand the role of PvpuCSP and its relatedness to the well-known CSP. The study revealed PvpuCSP as a membrane bound E3 ubiquitin ligase involved in ubiquitination. It has a species-specific tetra-peptide unit which is differentially repeated in various P. vivax strains. The PvpuCSP is different from CSP in terms of stage-specific expression and function. Since E3 ubiquitin ligases are known antimalarial drug targets targeting the proteasome pathway, PvpuCSP, with evolutionary connotation and a key role in orchestrating protein degradation in P. vivax, can be explored as a potential drug target.

Breast cancer is the most common female malignancy and the major cause of cancer-related death in women. Long non-coding RNAs (lncRNAs), as oncogenic or tumor suppressor factor, involved in the development and progression of various cancers. In this study, we sought to investigate the function of lncRNA CBR3-AS1 in breast cancer. We evaluated the expression pattern of CBR3-AS1 in breast cancer tissues and cell lines, explored the correlation between CBR3-AS1 expression and the survival time of breast cancer patients, and probed the effect of CBR3-AS1 on tumor progression of breast cancer through loss-of-function and gain-of-function strategies. Our results showed that CBR3-AS1 was overexpressed in breast cancer tissues and cell lines and predicted the prognosis of breast cancer patients. And CBR3-AS1 exerted biological function as an oncogenic lncRNA, involved in the regulation of cell proliferation, colony formation, apoptosis and tumor growth in breast cancer. Taken together, CBR3-AS1 was up-regulated in breast cancer and promoted the risk of breast cancer. It may be a novel therapeutic target and potential prognostic marker for breast cancer.