3'-UTRmiRNAs (microRNAs) are short non-coding RNAs that regulate gene expression post-transcriptionally. They generally bind to the 3'-UTR (untranslated region) of their target mRNAs and repress protein production by destabilizing the mRNA and translational silencing.
MicroRNA as pointed out and clearly demonstrated via multiple parallel sequencing can bind to 3'UTR, 5'UTR and coding regions too. You have to enlarge the classical (old) vision of microRNA as simple regulators of transcription.
mRNA formed in the nucleus is transported out of the nucleus and into the cytoplasm where it attaches to the ribosomes. Proteins are assembled on the ribosomes using the mRNA nucleotide sequence as a guide. Thus mRNA carries a “message” from the nucleus to the cytoplasm.
mRNA codons are read from 5' to 3' , and they specify the order of amino acids in a protein from N-terminus (methionine) to C-terminus. The mRNA sequence is: 5'-AUGAUCUCGUAA-5'
Definition. RNA-induced silencing complex, or RISC, is a multiprotein complex that incorporates one strand of a small interfering RNA (siRNA) or micro RNA (miRNA). RISC uses the siRNA or miRNA as a template for recognizing complementary mRNA. When it finds a complementary strand, it activates RNase and cleaves the RNA.
RISC contains Dicer, Argonaute proein, siRNA and other components. Researching structures and functions of these components is primary important for understanding assembly and functional mechanism of RISC, as well as the whole RNAi pathway.
Transfer RNA (tRNA) molecules serve as molecular adaptors that bind to mRNA on one end and carry amino acids into position on the other. Most types of cells possess approximately 30 to 40 different tRNAs, with more than one tRNA corresponding to each amino acid.
RNA-binding proteins (often abbreviated as RBPs) are proteins that bind to the double or single stranded RNA in cells and participate in forming ribonucleoprotein complexes. RBPs contain various structural motifs, such as RNA recognition motif (RRM), dsRNA binding domain, zinc finger and others.
Translation is the process of synthesis of protein from RNA. In translation, messenger RNA (mRNA) produced by transcription is decoded by the ribosome to produce a specific amino acid chain, or polypeptide, that will later fold into an active protein.
DNA utilizes four bases, adenine (A), guanine (G), cytosine (C), and thymine (T), in its code. RNA also uses four bases. However, instead of using 'T' as DNA does, it uses uracil (U). Therefore, if your DNA sequence is 3' T C G T T C A G T 5', the mRNA sequence would be 5' A G C A A G U C A 3'.Jan 7, 2022
DNACoding Strand (Codons)5' > > > - - - - - - T T C - - - - - - > > > 3'Template Strand (Anti-codons)3' < < < - - - - - - A A G - - - - - - < < < 5'mRNAMessage (Codons)5' > > > - - - - - - U U C - - - - - - > > > 3'tRNATranfer (Anti-codons)3' < < < A A G < < < 5'ProteinAmino AcidAmino > > > Phenylalanine > > > Carboxy
The ribosome initially moves down the transcript one base at a time, reading the sequence in three-base words known as codons (Fig. 3.17). The ribosome starts translation, the assembly of a protein out of amino acids, when it encounters the start codon in the mRNA, which is the sequence AUG.