Alternative transcription start site (TSS) usage regulation has been identified as a major means of gene expression regulation in metazoans. However, in fungi, its impact remains elusive as its study has thus far been restricted to model yeasts. Here, we first re-analyzed TSS-seq data to define genuine TSS clusters in 2 species of pathogenic Cryptococcus.
View Article and Find Full Text PDFPathogenic fungi require delicate gene regulation mechanisms to adapt to diverse living environments and escape host immune systems. Recent advances in sequencing technology have exposed the complexity of the fungal genome, thus allowing the gradual disentanglement of multiple layers of gene expression control. Alternative transcription start site (aTSS) usage, previously reported to be prominent in mammals and to play important roles in physiopathology, is also present in fungi to fine-tune gene expression.
View Article and Find Full Text PDFimaginal discs are larval internal structures that become the external organs of the adult. They have been used to study numerous developmental processes for more than fifty years. Dissecting these imaginal discs for collection is challenging, as the size of third-instar larvae organs is typically less than 1 mm.
View Article and Find Full Text PDFDetecting protein-RNA interactions in vivo is essential for deciphering many important cellular pathways. Several methods have been described for this purpose, among which cross-linking analysis of cDNA, CRAC. This method relies on a first step of UV cross-linking of living yeast cells and several subsequent steps of purification of the protein-RNA complexes, some of which under denaturing condition.
View Article and Find Full Text PDFApoptosis is associated with numerous phenotypical characteristics, and is thus studied with many tools. In this study, we compared two broadly used apoptotic assays: TUNEL and staining with an antibody targeting the activated form of an effector caspase. To compare them, we developed a protocol based on commonly used tools such as image filtering, z-projection, and thresholding.
View Article and Find Full Text PDFTranscription termination delimits transcription units but also plays important roles in limiting pervasive transcription. We have previously shown that transcription termination occurs when elongating RNA polymerase II (RNAPII) collides with the DNA-bound general transcription factor Reb1. We demonstrate here that many different DNA-binding proteins can induce termination by a similar roadblock (RB) mechanism.
View Article and Find Full Text PDFIt is now well established that the mitochondrion is a central regulator of mammalian cell apoptosis. However, the importance of this organelle in non-mammalian apoptosis has long been regarded as minor, mainly because of the absence of a crucial role for cytochrome c in caspase activation. Recent results indicate that the control of caspase activation and cell death in Drosophila occurs at the mitochondrial level.
View Article and Find Full Text PDFMembers of the Bcl-2 family are key elements of the apoptotic machinery. In mammals, this multigenic family contains about twenty members, which either promote or inhibit apoptosis. We have previously shown that the mammalian pro-apoptotic Bcl-2 family member Bax is very efficient in inducing apoptosis in Drosophila, allowing the study of bax-induced cell death in a genetic animal model.
View Article and Find Full Text PDFWidely transcribed compact genomes must cope with the major challenge of frequent overlapping or concurrent transcription events. Efficient and timely transcription termination is crucial to control pervasive transcription and prevent transcriptional interference. In yeast, transcription termination of RNA polymerase II (RNAPII) occurs via two possible pathways that both require recognition of termination signals on nascent RNA by specific factors.
View Article and Find Full Text PDFThe ubiquitin-proteasome system is one of the main proteolytic pathways. It inhibits apoptosis by degrading pro-apoptotic regulators, such as caspases or the tumor suppressor p53. However, it also stimulates cell death by degrading pro-survival regulators, including IAPs.
View Article and Find Full Text PDFRecent studies on yeast transcriptome have revealed the presence of a large set of RNA polymerase II transcripts mapping to intergenic and antisense regions or overlapping canonical genes. Most of these ncRNAs (ncRNAs) are subject to termination by the Nrd1-dependent pathway and rapid degradation by the nuclear exosome and have been dubbed cryptic unstable transcripts (CUTs). CUTs are often considered as by-products of transcriptional noise, but in an increasing number of cases they play a central role in the control of gene expression.
View Article and Find Full Text PDFJ Psychosoc Nurs Ment Health Serv
February 2010
Individuals who have maladaptive patterns of drinking alcohol fall into the category of vulnerable research participants for many reasons, not the least of which includes the stigma often placed on individuals who abuse alcohol. Vulnerable subgroups within the population of people who abuse alcohol include women; older adults; incarcerated, socioeconomically disadvantaged, and mentally ill individuals; as well as people from racial minorities. Thus, as research participants, individuals who abuse alcohol can be labeled a doubly vulnerable population.
View Article and Find Full Text PDFThe purpose of this study was to determine the effects of an osteoporosis educational intervention on knowledge, health beliefs, and self-efficacy in college-age Puerto Rican women. The Health Belief Model and Purnell Model formed the theoretical framework for the study. Three hypotheses were tested with a convenience, randomized sample of 51 experimental and 54 control subjects, ages 18-25.
View Article and Find Full Text PDFThe Institute of Medicine (IOM) has recommended that more minorities be represented in the health care workforce and that cross-cultural education be included in all health care programs (Betancourt, J.R., & Maina, A.
View Article and Find Full Text PDFDespite public health campaigns and safer sex messages, many men who have sex with men (MSM) continue to participate in high-risk sexual behaviors, which may make them vulnerable to HIV infection and sexually transmitted infections. The purpose of this study was to determine the relationship of depressive symptoms, self-esteem, and sexual behaviors in a predominantly Hispanic sample of MSM. This correlational study sampled 205 MSM (M = 37 years of age, SD = +/-8) representing the diverse ethnic composition of South Florida.
View Article and Find Full Text PDFFront Biosci (Landmark Ed)
January 2009
Initiator caspases are activated within specialized complexes, one of which is the apoptosome. The apoptosome is always constituted by at least an initiator caspase and a caspase activator. Apoptosome activation enables maturation of the associated caspase and constitutes a key step for cell fate.
View Article and Find Full Text PDFHidden transcription in eukaryotes carries a large potential of regulatory functions that are only recently beginning to emerge. Cryptic unstable transcripts (CUTs) are generated by RNA polymerase II (Pol II) and rapidly degraded after transcription in wild-type yeast cells. Whether CUTs or the act of transcription without RNA production have a function is presently unclear.
View Article and Find Full Text PDFCotranscriptional loading of proteins onto nascent transcripts contributes to the formation of messenger ribonucleoprotein particles (mRNPs) competent for nuclear export. The transcription machinery is believed to play a pivotal role in mRNP assembly, which is at least partially linked to the function of the THO/TREX complex and the mRNA termination/polyadenylation apparatus. Here we demonstrate a prominent role for the rate of transcription in the production of export-competent mRNPs.
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