Related Experiment Video
Updated: May 1, 2026

Determination of DNA Methylation of Imprinted Genes in Arabidopsis Endosperm
Published on: January 29, 2011
Methylated blocked 5' terminal sequences of sea urchin embryo messenger RNA classes containing and lacking poly(A)
Abstract:
Sea urchin embryo mRNAs of three distinct classes--histone mRNA, nonhistone mRNA containing poly(A), "[+A] mRNA," and nonhistone mRNA lacking poly(A), "[-A]mRNA"--all contain blocked 5' terminal sequences in which 7-methylguanosine is linked 5'-5' via a triphosphate bridge to a 2'-0-methylated nucleotide. Only one general type of 5' terminal structure, 7mGpppXmpYp, is present. Additional 2'-0-methylation in the Y residue has not been found either in early or late stage embryos. A substantial proportion of the polyribosomal mRNAs in all three classes contain this blocked structure. Whereas both classes of nonhistone mRNAs have internal base methylations, histone mRNAs lack such modifications.
Related Concept Videos
MicroRNAs
pre-mRNA Processing
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl...
RNA Editing
mRNA Stability and Gene Expression
Cis-acting Elements involved in mRNA stability
Pre-mRNA Processing: Modification of pre-mRNA Ends
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a cap to the 5' end of the growing transcript. In this process, a 5' phosphate is replaced by modified guanosine that has a methyl group attached (7-methyl guanosine). This 5' cap helps...
MicroRNAs

