10BIS1012013EuKTranscLect10

This is followed by methylation of guanine at

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: out of the nucleus into the cytoplasm. cytoplasm. BIS101­001, Spring 2013—Genes and Gene Expression, R.L. Rodriguez ©2013 BIS101­001, Spring 2013—Genes and Gene Expression, R.L. Rodriguez 17 Eukaryotic Transcripton: Capping ­ After the nascent (newly synthesized) hnRNA molecule has After grown to between 20 and 30 bases, the enzyme guanylyl transferase binds to the end of the hnRNA and adds a transferase guanine residue to the 5'pppA via a 5'-5' phosphodiester bond. ­ This is followed by methylation of guanine at position 7’ by by purine-7‘-methylase and position 2’ of the first adenine in purine-7 the RNA by and purine-2‘-methylase. The result of these purine-2 The reactions is a 7mG5’ppp5‘A2m at the end of the hnRNA. This is called the “cap.” is ­ The cap may function to protect the 5' end of the RNA from The degradation by exoribonucleases, and it may help in binding exoribonucleases and the mRNA to the ribosome. the BIS101­001, Spring 2013—Genes and Gene Expression, R.L. Rodriguez ©2013 BIS101­001, Spring 2013—Ge...
View Full Document

This note was uploaded on 02/12/2014 for the course BIS 101 taught by Professor Simonchan during the Spring '08 term at UC Davis.

Ask a homework question - tutors are online