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Role of RppH (RNA pyrophosphorylase) in mRNA degradation


Messenger RNA turnover is important for levels of transcripts and overall expression of genes. To date, a number of proteins involved in mRNA turnover have been identified. One of these proteins is an RNA pyrophosphohydrolase (RppH). It has been shown in bacteria that this enzyme converts triphosphorylated RNA 5’ ends into monophosphorylated ends, thereby probably initiating mRNA degradation in bacteria.

An RNA pyrophosphorylase is present in cells of the unicellular green alga Chlamydomonas but its role in mRNA turnover is not clear. We want to study the role of the Chlamydomonas RppH in mRNA degradation by repressing its expression by artificial microRNAs and monitoring the effect of the repression on mRNA turnover. The work involves making an artificial microRNA construct, inserting the microRNA gene stably into the nuclear genome of Chlamydomonas, screening for transformants, analyzing the transformants for levels of repression of RppH synthesis, and determining the effect of repression on mRNA turnover.


Relevant reading:

Salvador ML, Suay L, and Klein U (2011) Messenger RNA degradation is initiated at the 5’ end and follows sequence- and condition-dependent modes in chloroplasts. Nucleic Acids Res. 39 (14), 6213-6222.

Deana A, Celesnik H and Belasco JG (2008) The bacterial enzyme RppH triggers messenger RNA degradation by 5’ pyrophosphate removal. Nature 451, 355-359.

Suay L, Salvador ML, Abesha E and Klein U (2005) Specific roles of 5’ RNA secondary structures in stabilizing transcripts in chloroplasts. Nucleic Acids Res. 33, 4754-4761.

Publisert 12. sep. 2011 13:47 - Sist endret 13. des. 2011 13:28


Omfang (studiepoeng)