What is lin-4 gene?
lin-4 is essential for the normal temporal control of diverse postembryonic developmental events in C. elegans. lin-4 acts by negatively regulating the level of LIN-14 protein, creating a temporal decrease in LIN-14 protein starting in the first larval stage (L1).
Is lin-4 a miRNA?
In molecular biology lin-4 is a microRNA (miRNA) that was identified from a study of developmental timing in the nematode Caenorhabditis elegans. It was the first to be discovered of the miRNAs, a class of non-coding RNAs involved in gene regulation.
Which of the following is discovered as first small RNA in C elegans?
MicroRNAs (miRNAs) were first discovered in C. elegans. The lin-4 gene, known to control the timing of C. elegans larval development, was found not to encode for a protein, but for a small RNA.
What are the Lin 4 and Lin 14 genes of C elegans?
Two small lin-4 transcripts of approximately 22 and 61 nt were identified in C. elegans and found to contain sequences complementary to a repeated sequence element in the 3′ untranslated region (UTR) of lin-14 mRNA, suggesting that lin-4 regulates lin-14 translation via an antisense RNA-RNA interaction.
What are Heterochronic genes?
Heterochronic refers to the development of cells or tissues at an abnormal time relative to other unaffected events in an organism; the latter can thus serve as temporal landmarks. Mutations in heterochronic genes cause certain cells to adopt cell fates normally associated with earlier or later times in development.
What is PRI miRNA?
MicroRNAs (miRNAs) are small, regulatory RNAs that are expressed in animals and plants and affect the translation or stability of target mRNAs. The 17-24 nt, single-stranded (ss) miRNAs are derived from longer, primary transcripts termed “pri-miRNAs” [1].
What are the Lin 4 and Lin 14 genes of C. elegans?
How is dsRNA formed?
The production of double-stranded RNA (dsRNA) in eukaryotic cells, generally as the result of viral replication or the transcription of transposable elements and repetitive DNA sequences, is known to elicit two types of cellular defense responses.
What is an ortholog Gene?
Orthologs are genes in different species that evolved from a common ancestral gene by speciation, and, in general, orthologs retain the same function during the course of evolution. Identification of orthologs is a critical process for reliable prediction of gene function in newly sequenced genomes.
What is the difference between PRI-miRNA and pre miRNA?
The hairpin, which typically comprises 60-120 nt, is cleaved from the pri-miRNA in the nucleus by the double-strand-specific ribonuclease, Drosha [1]. The resulting precursor miRNA, or “pre-miRNA,” is transported to the cytoplasm via a process that involves Exportin-5 [2-4].
What is a hairpin RNA?
A hairpin loop is an unpaired loop of messenger RNA (mRNA) that is created when an mRNA strand folds and forms base pairs with another section of the same strand. The resulting structure looks like a loop or a U-shape. Hairpins are a common type of secondary structure in RNA molecules.
How many miRNAs are there in humans?
There are now over 2000 miRNAs that have been discovered in humans and it is believed that they collectively regulate one third of the genes in the genome. miRNAs have been linked to many human diseases and are being pursued as clinical diagnostics and as therapeutic targets.
What is the function of lin-4 in C elegans?
lin-4 is essential for the normal temporal control of diverse postembryonic developmental events in C. elegans. lin-4 acts by negatively regulating the level of LIN-14 protein, creating a temporal decrease in LIN-14 protein starting in the first larval stage (L1).
Is lin-4 a microRNA?
Predicted secondary structure and sequence conservation of lin-4. In molecular biology lin-4 is a microRNA (miRNA) that was identified from a study of developmental timing in the nematode Caenorhabditis elegans. It was the first to be discovered of the miRNAs, a class of non-coding RNAs involved in gene regulation.
What does lin-4 stand for?
In molecular biology lin-4 is a microRNA (miRNA) that was identified from a study of developmental timing in the nematode Caenorhabditis elegans.
What are the effects of lin-4 and lin-14 inhibitors?
Consequences include heterochronic developmental patterns, with loss of structures such as the vulva and adult cuticle. lin-4 acts as a negative regulator of lin-14 and represses accumulation of the LIN-14 protein. It also targets lin-28 and reduces its protein expression through translational inhibition.