Essay On Circrna

Recent advantages in genome-wide analyses have revealed that roughly 90% of the human genome is transcribed, yet less than 3% of the genome consists of protein-coding genes (Wu et al., 2013). The remaining genes are transcribed as noncoding RNAs (ncRNAs), which resemble mRNA in length and splicing structures yet do not encode any proteins (Wu et al., 2013). It has been debated whether all of the ncRNA transcripts are functional due to their low expression levels and low evolutionary conservation. However, many functional ncRNA have

Structurally, miRNAs are initially transcribed from the genome as a long primary transcript that are cleaved or undergoes sequential processing by the RNAse III endonucleases Drosha and Dicer to yield the 17-23 mature nucleotide species (Kim, 2005). Mature miRNAs enters the RNA-induced silencing complex (RISC), thus a multiprotein complex that separate the mature strand from passenger strand and assists the interaction of mRNAs with miRNA that contain complementary sequences (Bader, 2012). As a result, mRNAs targeted by miRNA loads are either degraded or silenced in order not to be translated into protein. In the genome, a given miRNA can regulate several hundred transcripts whose molecules function within various cellular pathways including cell proliferation and apoptosis. To date, more than 50% of the activities of all protein-coding genes in mammals are controlled by miRNAs and greatly contributes to cell-type specific profiles of protein expression

In the second paper, “Novel RNA Modifications in the Nervous System: Form and Function,” Lee discusses the role of several novel RNA modification in the physiological setting of the nervous system. RNA editing plays a major role in many pathologies; for example, loss of normal function in an m6a demethylase, FTO, has been connected with cancer, ADHD, and Alzheimer’s. Other RNA modifications are necessary for proper development of the central nervous system. NSUN2 is an m5C RNA modification heavily implicated in embryogenesis, especially in the brain. Mutation of the NSUN2 gene is correlated with intellectual disability, developmental delay, and facial dysmorphism. The aforementioned A-to-I RNA edit is also enriched in the brain, and is necessary for the proper function of genes such as GluA2, which without modification leads to postnatal death. GluA2 is also implicated in glutamate reception by neurons, and consequently in the mechanisms of addiction. Furthermore, A-to-I RNA editing failure been linked with several chronic diseases, including

This study shows that 6% of the entire annotated non-coding and coding gene transcripts are overlapping with small RNAs. Highly specific subcellular positioning is found for both unannotated & annotated short RNA.

The citole is a wooden, stringed instrument that resembles a primitive violin-guitar hybrid. Its musical technique is like that of a guitar; pitch change is controlled in the neck. Geoffrey Chaucer crafted The Canterbury Tales during an age when music was expressive and influential. Venus’s altar is vividly detailed in the Knight’s Tale, in part 3 of The Canterbury Tales. The beautiful statue of Venus is depicted holding a citole in her right hand. The inclusion of this small lyre-like instrument has a deep association and symbolic meaning. The citole has connections with angels, ethereality, and divinity.

The RNA-induced-silencing complex is used for gene regulation and in defense against viral and bacterial infections. The RISC is loaded with small dsRNAs that will guide the complex through base-pairing interactions to specific messenger RNA targets, which the RISC will help degrade. Once degraded, no more protein can be made from these mRNAs. The RNA-induced silencing complex can silence targeted genes through several mechanisms. It can work to repress translation during protein synthesis, interfere with the transcript level through mRNA degradation, or work at the level of the genome itself and eliminate DNA/form degrading materials. Heterochromatin is a degrading material that can be created to modify or suppress genes in the RISC (MacRae

In addition to increased DNA methylation, a typical WT response also includes post-transcriptional gene regulation by miRNAs. One of the miRNAs that are upregulated in the WT embryos in response to stress is miR-21c. miR-21c is expected to target Chromodomain Helicase DNA Binding Protein 7 (CHD7). Chd7 is a protein that through chromatin remodeling, regulates the gene expression of several genes. CHARGE syndrome, an ASD syndromic subtype, is the most common result of a CHD7 gene mutation10. This hypermethylation of the CHD7 gene in addition to the increased expression of miR-21c, collaborate and lead to reduced gene expression.

Long non-coding RNAs (lncRNAs) are a class of RNAs that are more than 200 nucleotides long (2) and do not encode proteins. LncRNAs regulate a spectrum of biological functions and their misregulation or differential expression contribute to tumerogenesis. Exploiting this feature of lncRNAs make them excellent candidates for cancer therapy. An important indication of cancer is metabolic reprogramming which is indicated by increase in various pathways in cells such as glycolysis, glutaminolysis, Pentose Phosphate Pathway, synthesis of nucleotide and fatty acids, and formation of citrate through TCA cycle (4). Prostate Cancer Gene expression marker 1 (PCGEM1) (3), is a lncRNA that control the reprogramming of metabolic pathways in prostate

Aim 2 - Identify whether differential patterns of expression between tumorigenic and normal tissues are distinguished by enrichment in repetitive and non-coding RNAs.

Both animal and clinical studies have demonstrated that obesity leads to ovarian dysfunction through oxidative and ER stress and inflammation (26,65,66,74-78). Obesity leads to excess lipids, glucose, insulin, and leptin in variety of ovarian cells including: granulosa cells, cumulus cells, oocytes, and early embryos (ref more;(65,79,80)). Because leptin contributes to follicular growth, steroidogenesis, oocyte maturation and embryo development, hyperleptinemia seen in obese women may disrupt these processes (30,58,70,75,78,81-96). Similarly, insulin resistance and or hyperinsulinemia, have been shown to alter ovarian morphology, ovarian insulin signaling, ovulation and maturation of oocytes (23,30,36,39,40,71,73,74,97-107). Obesity leads to elevated levels of circulating lipids as well as lipid accumulation in the ovary which are associated with decreased granulosa cell numbers, increased apoptosis, greater lipid accumulation in cumulus cells, decreased oocyte nuclear maturation, and changes in substrate metabolism and proliferation in embryos (18,36,55,63,65,67,75,79,90,92,108-112). Greater oxidative stress and chronic low grade inflammation, as seen in obese animals and humans, have also been shown to alter oocyte maturation and fertilization, embryo development and pregnancy success (19,26,65,66,68,69,74,77,78,104,105,109,110,113-120). Lastly, obesity leads to a variety of oocyte mitochondrial defects, including

MicroRNA’s can affect the gene expression by preventing their translation onto protein. This blocking function lead to enabling the cells to adapt to change condition.

The invention of microscope in 1590 and biological observations in the mid-1960s allowed the advancement understanding of fertilization to implantation in the field of reproductive biology on a cellular level. The first studies made it clear that reproductive biology isn’t the same throughout the animal kingdom. Once better understood, those differences facilitated the making of the first IVF baby, Louise Brown in 1978. However, new technologies have been created in the field of clinical embryology since then and are briefly described in this paper. New procedures introduced new challenges, not yet fully understood in the field of epigenetics. Do ART procedures and micromanipulation cause a direct or indirect effect on epigenetic disruption in mammalian preimplantation embryos?

Some of the more interesting genomic locations of miRNA genes include those in the Hox clusters. The mir-10 gene lies in the Antennapedia complex of insects and in the orthologous locations in two Hox clusters of mammals [15, 16]. The Hox miRNAs are especially good candidates for having interesting functions in animal development. Nearly all of the cloned miRNAs are conserved in closely related animals such as human and mouse, or C. elegans and C. briggsae [16, 17]. Many mi RNAs are conserved concerved more broadly

In Archetype II lncRNA works to titrate proteins and protein factors away from chromatins, yet titrating them into nuclear subdomains while serving as decoys. This is common in miRNA sites where lncRNA appears as decoys. Acting as guides in Archetype III, lncRNA functions in either cis or trans regions to assist in the recruitment of chromatin enzymes for target genes. In cis, lncRNA occurs in co-transcriptionally. This suggests that lncRNAs acts as tethers. However, lncRNA are known to also act in trans when searching for target sites. This determines the importance chromosomal looping plays in cis effects (Rinn and Chang, 2012). During Archetype IV lncRNA forms ribonucleoproteins by acting as scaffolds (Kung, Colognori and Lee, 2013). Additionally, lncRNA in the regulation of gene expression was recent discovered in Xist, a regulatory transcript found in the X chromosome that mediates the silencing of gene expression (Malecová and Morris, 2010). According to Nagano and Fraser (2011), lncRNA is critical in genomic reprogramming. For instance, somatic cells that are reconditioned to induced pluripotent stem cells. LncRNA can also act as a post-transcriptional regulation in Mrna. A lncRNA known as Gomafu/MIAT hinders the formation of spliceosome and inhibits the splicing of one of the subsets involved in mRNA (Kung, Colognori and Lee, 2013).

sequence of the parent cell because as the chromosomes separate during anaphase and the cell splits