Browsing by Subject "3' Untranslated Regions"

Now showing 1 - 5 of 5

Open Access
A functional variant at miRNA-122 binding site in IL-1a 3' UTR predicts risk of recurrence in patients with oropharyngeal cancer.
(Oncotarget, 2016-06) Wang, Chengyuan; Sturgis, Erich M; Chen, Xingming; Wei, Qingyi; Li, Guojun
IL-1a, an important regulator of immune and inflammation responses, has been implicated in cancer development and prognosis. An insertion (Ins)/deletion (Del) polymorphism (IL-1a rs3783553) in the 3' UTR of IL-1a may disrupt a binding site for miRNA-122 and may affect its transcription level. Thus, this polymorphism may cause interindividual variation in immune and inflammation responses and thus may lead to different susceptibility to treatment response and prognosis of such patients. We evaluated the association of IL-1a rs3783553 polymorphism with risk of recurrence of squamous cell carcinoma of the oropharynx (SCCOP) in a cohort of 1008 patients. Log-rank test and univariate and multivariable Cox models were used to evaluate associations. Compared with patients with Del/Del homozygous genotype, the patients with Ins/Del+Ins/Ins variant genotypes had worse disease-free survival (log-rank P < 0.0001) and increased risk of SCCOP recurrence (HR, 2.4, 95% CI, 1.7-3.3) after multivariable adjustment. Furthermore, among patients with HPV16-positive tumors, the patients with Ins/Del+Ins/Ins variant genotypes of the IL-1a polymorphism had worse disease-free survival (log-rank P < 0.0001) and much higher recurrence risk than those with Del/Del homozygous genotype of this polymorphism (HR, 16.3, 95% CI, 5.0-52.7). Our findings suggest that IL-1a rs3783553 polymorphism may modulate the risk of SCCOP recurrence in patients, particularly for patients with HPV16-positive tumors. However, larger studies are needed to validate these results.
Unknown
MicroRNA antagonism of the picornaviral life cycle: alternative mechanisms of interference.
(PLoS Pathog, 2010-03-19) Kelly, Elizabeth J; Hadac, Elizabeth M; Cullen, Bryan R; Russell, Stephen J
In addition to modulating the function and stability of cellular mRNAs, microRNAs can profoundly affect the life cycles of viruses bearing sequence complementary targets, a finding recently exploited to ameliorate toxicities of vaccines and oncolytic viruses. To elucidate the mechanisms underlying microRNA-mediated antiviral activity, we modified the 3' untranslated region (3'UTR) of Coxsackievirus A21 to incorporate targets with varying degrees of homology to endogenous microRNAs. We show that microRNAs can interrupt the picornavirus life-cycle at multiple levels, including catalytic degradation of the viral RNA genome, suppression of cap-independent mRNA translation, and interference with genome encapsidation. In addition, we have examined the extent to which endogenous microRNAs can suppress viral replication in vivo and how viruses can overcome this inhibition by microRNA saturation in mouse cancer models.
Open Access
Nutritional control of mRNA isoform expression during developmental arrest and recovery in C. elegans.
(Genome Res, 2012-10) Maxwell, Colin S; Antoshechkin, Igor; Kurhanewicz, Nicole; Belsky, Jason A; Baugh, L Ryan
Nutrient availability profoundly influences gene expression. Many animal genes encode multiple transcript isoforms, yet the effect of nutrient availability on transcript isoform expression has not been studied in genome-wide fashion. When Caenorhabditis elegans larvae hatch without food, they arrest development in the first larval stage (L1 arrest). Starved larvae can survive L1 arrest for weeks, but growth and post-embryonic development are rapidly initiated in response to feeding. We used RNA-seq to characterize the transcriptome during L1 arrest and over time after feeding. Twenty-seven percent of detectable protein-coding genes were differentially expressed during recovery from L1 arrest, with the majority of changes initiating within the first hour, demonstrating widespread, acute effects of nutrient availability on gene expression. We used two independent approaches to track expression of individual exons and mRNA isoforms, and we connected changes in expression to functional consequences by mining a variety of databases. These two approaches identified an overlapping set of genes with alternative isoform expression, and they converged on common functional patterns. Genes affecting mRNA splicing and translation are regulated by alternative isoform expression, revealing post-transcriptional consequences of nutrient availability on gene regulation. We also found that phosphorylation sites are often alternatively expressed, revealing a common mode by which alternative isoform expression modifies protein function and signal transduction. Our results detail rich changes in C. elegans gene expression as larvae initiate growth and post-embryonic development, and they provide an excellent resource for ongoing investigation of transcriptional regulation and developmental physiology.
Open Access
Polymorphisms in thymidylate synthase gene and susceptibility to breast cancer in a Chinese population: a case-control analysis.
(BMC cancer, 2006-01) Zhai, Xiangjun; Gao, Jun; Hu, Zhibin; Tang, Jinhai; Qin, Jianwei; Wang, Shui; Wang, Xuechen; Jin, Guangfu; Liu, Jiyong; Chen, Wenshen; Chen, Feng; Wang, Xinru; Wei, Qingyi; Shen, Hongbing
BACKGROUND: Accumulative evidence suggests that low folate intake is associated with increased risk of breast cancer. Polymorphisms in genes involved in folate metabolism may influence DNA methylation, nucleotide synthesis, and thus individual susceptibility to cancer. Thymidylate synthase (TYMS) is a key enzyme that participates in folate metabolism and catalyzes the conversion of dUMP to dTMP in the process of DNA synthesis. Two potentially functional polymorphisms [a 28-bp tandem repeat in the TYMS 5'-untranslated enhanced region (TSER) and a 6-bp deletion/insertion in the TYMS 3'-untranslated region (TS 3'-UTR)] were suggested to be correlated with alteration of thymidylate synthase expression and associated with cancer risk. METHODS: To test the hypothesis that polymorphisms of the TYMS gene are associated with risk of breast cancer, we genotyped these two polymorphisms in a case-control study of 432 incident cases with invasive breast cancer and 473 cancer-free controls in a Chinese population. RESULTS: We found that the distribution of TS3'-UTR (1494del6) genotype frequencies were significantly different between the cases and controls (P = 0.026). Compared with the TS3'-UTR del6/del6 wild-type genotype, a significantly reduced risk was associated with the ins6/ins6 homozygous variant genotype (adjusted OR = 0.58, 95% CI = 0.35-0.97) but not the del6/ins6 genotype (OR = 1.09, 95% CI = 0.82-1.46). Furthermore, breast cancer risks associated with the TS3'-UTR del6/del6 genotype were more evident in older women, postmenopausal subjects, individuals with a younger age at first-live birth and individuals with an older age at menarche. However, there was no evidence for an association between the TSER polymorphism and breast cancer risks. CONCLUSION: These findings suggest that the TS3'-UTR del6 polymorphism may play a role in the etiology of breast cancer. Further larger population-based studies as well as functional evaluation of the variants are warranted to confirm our findings.
Unknown
The genome of a songbird.
(Nature, 2010-04-01) Warren, Wesley C; Clayton, David F; Ellegren, Hans; Arnold, Arthur P; Hillier, Ladeana W; Künstner, Axel; Searle, Steve; White, Simon; Vilella, Albert J; Fairley, Susan; Heger, Andreas; Kong, Lesheng; Ponting, Chris P; Jarvis, Erich D; Mello, Claudio V; Minx, Pat; Lovell, Peter; Velho, Tarciso AF; Ferris, Margaret; Balakrishnan, Christopher N; Sinha, Saurabh; Blatti, Charles; London, Sarah E; Li, Yun; Lin, Ya-Chi; George, Julia; Sweedler, Jonathan; Southey, Bruce; Gunaratne, Preethi; Watson, Michael; Nam, Kiwoong; Backström, Niclas; Smeds, Linnea; Nabholz, Benoit; Itoh, Yuichiro; Whitney, Osceola; Pfenning, Andreas R; Howard, Jason; Völker, Martin; Skinner, Bejamin M; Griffin, Darren K; Ye, Liang; McLaren, William M; Flicek, Paul; Quesada, Victor; Velasco, Gloria; Lopez-Otin, Carlos; Puente, Xose S; Olender, Tsviya; Lancet, Doron; Smit, Arian FA; Hubley, Robert; Konkel, Miriam K; Walker, Jerilyn A; Batzer, Mark A; Gu, Wanjun; Pollock, David D; Chen, Lin; Cheng, Ze; Eichler, Evan E; Stapley, Jessica; Slate, Jon; Ekblom, Robert; Birkhead, Tim; Burke, Terry; Burt, David; Scharff, Constance; Adam, Iris; Richard, Hugues; Sultan, Marc; Soldatov, Alexey; Lehrach, Hans; Edwards, Scott V; Yang, Shiaw-Pyng; Li, Xiaoching; Graves, Tina; Fulton, Lucinda; Nelson, Joanne; Chinwalla, Asif; Hou, Shunfeng; Mardis, Elaine R; Wilson, Richard K
The zebra finch is an important model organism in several fields with unique relevance to human neuroscience. Like other songbirds, the zebra finch communicates through learned vocalizations, an ability otherwise documented only in humans and a few other animals and lacking in the chicken-the only bird with a sequenced genome until now. Here we present a structural, functional and comparative analysis of the genome sequence of the zebra finch (Taeniopygia guttata), which is a songbird belonging to the large avian order Passeriformes. We find that the overall structures of the genomes are similar in zebra finch and chicken, but they differ in many intrachromosomal rearrangements, lineage-specific gene family expansions, the number of long-terminal-repeat-based retrotransposons, and mechanisms of sex chromosome dosage compensation. We show that song behaviour engages gene regulatory networks in the zebra finch brain, altering the expression of long non-coding RNAs, microRNAs, transcription factors and their targets. We also show evidence for rapid molecular evolution in the songbird lineage of genes that are regulated during song experience. These results indicate an active involvement of the genome in neural processes underlying vocal communication and identify potential genetic substrates for the evolution and regulation of this behaviour.