RESUMEN
The waste of food presents a challenge for achieving a sustainable world. In Germany alone, over 10 million tonnes of food are discarded annually, with a worldwide total exceeding 1.3 billion tonnes. A significant contributor to this issue are consumers throwing away still edible food due to the expiration of its best-before date. Best-before dates currently include large safety margins, but more precise and cost effective prediction techniques are required. To address this challenge, research was conducted on low-cost sensors and machine learning techniques were developed to predict the spoilage of fresh pizza. The findings indicate that combining a gas sensor, such as volatile organic compounds or carbon dioxide, with a random forest or extreme gradient boosting regressor can accurately predict the day of spoilage. This provides a more accurate and cost-efficient alternative to current best-before date determination methods, reducing food waste, saving resources, and improving food safety by reducing the risk of consumers consuming spoiled food.
RESUMEN
Intergenic transcription is a common feature of eukaryotic genomes and performs important and diverse cellular functions. Here, we investigate the iab-8 ncRNA from the Drosophila Bithorax Complex and show that this RNA is able to repress the transcription of genes located at its 3' end by a sequence-independent, transcriptional interference mechanism. Although this RNA is expressed in the early epidermis and CNS, we find that its repressive activity is limited to the CNS, where, in wild-type embryos, it acts on the Hox gene, abd-A, located immediately downstream of it. The CNS specificity is achieved through a 3' extension of the transcript, mediated by the neuronal-specific, RNA-binding protein, ELAV. Loss of ELAV activity eliminates the 3' extension and results in the ectopic activation of abd-A. Thus, a tissue-specific change in the length of a ncRNA is used to generate a precise pattern of gene expression in a higher eukaryote.
Asunto(s)
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas ELAV/genética , Genes Homeobox , Proteínas Nucleares/genética , Factores de Transcripción/genética , Transcripción Genética , Animales , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Drosophila melanogaster/embriología , Genes Reporteros , MicroARNs/genética , ARN Largo no Codificante/genética , Eliminación de SecuenciaRESUMEN
Colorectal cancer (CRC) is a leading cause of cancer-related morbidity and mortality. In a cohort of 189 patients with CRC, we recently showed that expression of the cytoskeletal scaffolding protein non-erythroid spectrin αII (SPTAN1) was lower in advanced metastatic tumours. The aim of the present study was to clarify the association of intratumoural SPTAN1 expression levels with treatment and survival outcomes in patients with CRC. The analysis was based on histologic assessment of SPTAN1 protein levels in our own CRC cohort, and transcriptome data of 573 CRC cases from The Cancer Genome Atlas (TCGA). We first establish that high intratumoural levels of SPTAN1 protein and mRNA associate with favourable survival outcomes in patients with CRC. Next, a response prediction signature applied to the TCGA data reveals a possible link between high SPTAN1 transcript levels and improved patient responses to FOLFOX chemotherapy. Complementary in vitro experiments confirm that SPTAN1 knockdown strains of the colon cancer cell lines HT-29, HCT116 mlh1-2 and Caco-2 are less responsive to FOLFOX chemotherapy compared with SPTAN1-proficient control strains. Taken together, we identify SPTAN1 as a novel prognostic biomarker in CRC and show that SPTAN1 expression levels may predict patient responses to chemotherapy. These investigations illustrate how an affordable, histology-based diagnostic test could directly impact therapeutic decision-making at the bedside.
RESUMEN
BACKGROUND: Transcriptional elongation is a generic function, but is also regulated to allow rapid transcription responses. Following relatively long initiation and promoter clearance, RNA polymerase II can pause and then rapidly elongate following recruitment of positive elongation factors. Multiple elongation complexes exist, but the role of specific components in adult Drosophila is underexplored. RESULTS: We conducted RNA-seq experiments to analyze the effect of RNAi knockdown of Suppressor of Triplolethal and lilliputian. We similarly analyzed the effect of expressing a dominant negative Cyclin-dependent kinase 9 allele. We observed that almost half of the genes expressed in adults showed reduced expression, supporting a broad role for the three tested genes in steady-state transcript abundance. Expression profiles following lilliputian and Suppressor of Triplolethal RNAi were nearly identical raising the possibility that they are obligatory co-factors. Genes showing reduced expression due to these RNAi treatments were short and enriched for genes encoding metabolic or enzymatic functions. The dominant-negative Cyclin-dependent kinase 9 profiles showed both overlapping and specific differential expression, suggesting involvement in multiple complexes. We also observed hundreds of genes with sex-biased differential expression following treatment. CONCLUSION: Transcriptional profiles suggest that Lilliputian and Suppressor of Triplolethal are obligatory cofactors in the adult and that they can also function with Cyclin-dependent kinase 9 at a subset of loci. Our results suggest that transcriptional elongation control is especially important for rapidly expressed genes to support digestion and metabolism, many of which have sex-biased function.
Asunto(s)
Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Perfilación de la Expresión Génica , Caracteres Sexuales , Factores de Elongación Transcripcional/metabolismo , Animales , Drosophila melanogaster/fisiología , Femenino , Técnicas de Silenciamiento del Gen , MasculinoRESUMEN
The GAGA factor (GAF), encoded by the Trithorax like gene (Trl) is a multifunctional protein involved in gene activation, Polycomb-dependent repression, chromatin remodeling and is a component of chromatin domain boundaries. Although first isolated as transcriptional activator of the Drosophila homeotic gene Ultrabithorax (Ubx), the molecular basis of this GAF activity is unknown. Here we show that dmTAF3 (also known as BIP2 and dTAF(II)155), a component of TFIID, interacts directly with GAF. We generated mutations in dmTAF3 and show that, in Trl mutant background, they affect transcription of Ubx leading to enhancement of Ubx phenotype. These results reveal that the gene activation pathway involving GAF is through its direct interaction with dmTAF3.
Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiología , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Factor de Transcripción TFIID/metabolismo , Factores de Transcripción/metabolismo , Activación Transcripcional/fisiología , Animales , Inmunoprecipitación de Cromatina , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas de Homeodominio/metabolismo , Modelos Genéticos , Mutagénesis , Factor de Transcripción TFIID/genética , Activación Transcripcional/genéticaRESUMEN
The Su(var)3-7 gene, a haplo-suppressor and triplo-enhancer of position-effect variegation (PEV), encodes a zinc finger heterochromatin-associated protein. To understand the role of this protein in heterochromatin and genomic silencing, mutations were generated by homologous recombination. The donor fragment contained a yellow(+) gene and 7.6 kb of the Su(var)3-7 gene inserted between two FRTs. The Su(var)3-7 sequence contained three stop codons flanking an I-SceI cut site located in the 5' half of the gene. Using two different screening approaches, we obtained an allelic series composed of three mutant alleles. The three mutations are dominant suppressors of PEV. One behaves as a null mutation and results in a maternal-effect recessive lethal phenotype that can be rescued by a zygotic paternal wild-type gene. A P transposon zygotically expressing a Su(var)3-7 full-length cDNA also rescues the mutant phenotype. One hypomorphic allele is viable and the pleiotropic phenotype showed by adult flies indicates that rapidly and late dividing cells seem the most affected by reduced amounts of Su(var)3-7 protein. All three mutants were characterized at the molecular level. Each expresses a portion of the Su(var)3-7 protein that is unable to enter the nucleus and bind chromatin.