Mapping of the binding domains of the Newcastle disease virus phosphoprotein in P–L and P–(NP-RNA) complexes

Abstract number: P767

Jahanshiri F., Yusoff K., Abdulah J., Abdul rahim R.

Newcastle disease virus (NDV) is an avian pathogen which affects the poultry industry worldwide. Outbreaks of the disease known as Newcastle disease (ND) often result in mass culling of the infected chickens. NDV has also oncolytic activities against human malignancies which lead to tumour apoptosis and cell death. Besides that NDV can serve as a viral vector to express and deliver foreign genes which is useful in vaccination and gene therapy. To identify the mechanisms involved in NDV pathogenesis as well as its anti cancer properties, the understanding of the mechanisms involved in the transcription and replication of the virus is of fundamental importance. One way to characterise such mechanisms is to identify the involvement of the viral proteins and their interacting partners. It has been shown in other paramyxovirues that the phosphoprotein (P) plays a central role in the transcription and the replication of the viral genome. Together with the large (L) protein, it forms and stabilizes the active RNA-dependent RNA polymerase complex. It also mediates the interaction between the L protein subunit of this complex with the viral nucelocapsid (NP-RNA) template comprising a nucleocapsid tightly bound RNA genome. Employing a yeast-two hybrid system the presence of P-L interaction in NDV was investigated. However, due to the low expression level of L protein yeast, no interaction was observed. Therefore, an in vitro co-translation approach was carried out to identify P-L interaction. The result showed that NDV P protein is also involved in the stabilisation of L protein. To identify the presence of NDV P–(NP-RNA) interaction and the involved domain(s), co-immunoprecipitation was performed. Purified NP:-RNA template along with in vitro translated P or its derivatives were separately co-immunoprecipitated using anti-His antibody. The results revealed that the immediate N-terminal of P protein is involved in its interaction with NP-RNA template.

In conclusion, the current study has delineated the key interacting partners of NDV P. This knowledge will be useful for structural and functional exploration of this protein.

Session Details

Date: 19/04/2008
Time: 00:00-00:00
Session name: 18th European Congress of Clinical Microbiology and Infectious Diseases
Location: Barcelona, Spain
Presentation type:
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