The nuclear factor-Kappa B (NF-κB) pathway is a crucial mediator of inflammatory signaling. Aberrant activation of NF-κB is associated with several disorders including preeclampsia (PE). Many regulators of the NF-κB pathway have been identified, including microRNAs (miRNAs).
View Article and Find Full Text PDFMicroRNAs (miRNAs) are ∼22 nt small noncoding RNAs that control gene expression at the posttranscriptional level through translational inhibition and destabilization of their target mRNAs. The biogenesis of miRNAs involves a series of processing steps beginning with cropping of the primary miRNA transcript by the Microprocessor complex, which is composed of Drosha and DGCR8. Here we report a novel regulatory interaction between the Microprocessor components and coilin, the Cajal body (CB) marker protein.
View Article and Find Full Text PDFHypoxia is a severe stressor to cellular homeostasis. At the cellular level, low oxygen triggers the transcription of a variety of genes supporting cell survival and oxygen homeostasis mediated by transcription factors, such as hypoxia-inducible factors (HIFs). Among many determinants dictating cell responses to hypoxia and HIFs are microRNAs (miRNAs).
View Article and Find Full Text PDFPolycystic ovary syndrome (PCOS) is the most common endocrine disorder in reproductive-age women. PCOS is characterized by hyperandrogenism and ovulatory dysfunction. Women with PCOS have a high prevalence of obesity, insulin resistance (IR), increased blood pressure (BP), and activation of the renin angiotensin system (RAS).
View Article and Find Full Text PDFThe Cajal body (CB) is a subnuclear domain that participates in the biogenesis of many different types of ribonucleoproteins (RNPs), including small nuclear RNPs (snRNPs), small Cajal body-specific RNPs (scaRNPs) and telomerase. Most scaRNAs, the RNA component of scaRNPs, accumulate in CBs. However, there are three scaRNAs (scaRNA 2, 9, and 17) that are known to be processed into small, nucleolar-enriched fragments.
View Article and Find Full Text PDFCajal bodies (CBs) are subnuclear domains involved in the formation of ribonucleoproteins (RNPs) including small nuclear RNPs (snRNPs). CBs associate with specific gene loci, which impacts expression and provides a platform for the biogenesis of the nascent transcripts emanating from these genes. Here we report that CBs can associate with the C19MC microRNA (miRNA) gene cluster, which suggests a role for CBs in the biogenesis of animal miRNAs.
View Article and Find Full Text PDFThe most common types of modification in human rRNA are pseudouridylation and 2'- ribose methylation. These modifications are performed by small nucleolar ribonucleoproteins (snoRNPs) which contain a guide RNA (snoRNA) that base pairs at specific sites within the rRNA to direct the modification. rRNA modifications can vary, generating ribosome heterogeneity.
View Article and Find Full Text PDFSmall Cajal body-specific RNAs (scaRNAs) are part of small Cajal body-specific ribonucleoproteins (scaRNPs) that modify small nuclear RNA (snRNA) in Cajal bodies (CBs). Several scaRNAs (scaRNA 2, 9 and 17) have been found to generate smaller, nucleolus-enriched fragments. We hypothesize that the fragments derived from scaRNA 2, 9 and 17 form regulatory RNPs that influence the level of modifications within rRNA by altering small nucleolar RNP (snoRNP) activity.
View Article and Find Full Text PDFRibosomes can be heterogeneous, and the major contributor to ribosome heterogeneity is variation in rRNA modification. There are two major types of rRNA modification, pseudouridylation and ribose methylation. In humans, the majority of these rRNA modifications are conducted by two classes of small nucleolar ribonucleoproteins (snoRNPs), which contain a guide RNA (small nucleolar RNA, snoRNA) complexed with proteins.
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