Molecular Characterization and Gene Expression Profiling ... - CUSAT

Chapter 4
gene transcripts were found to increase considerably during the
experimental period (Fig. 4.17).
Expression profile of thymidine kinase gene
Endonuclease gene could also be detected from 2 nd PCD onwards.
From 5 th PCD onwards the gene transcripts were found to increase
considerably during the late hours of WSSV challenge (Fig 4.18).
Expression profile of VP28 gene
Transcripts of VP28 gene could be detected from PCD 1 onwards.
However, only very low level of expression of the DNA polymerase gene
could be detected until 4 th PCD. After that, the gene transcripts were found
to be increased considerably during the experimental period (Fig. 4.19).
4.4. Discussion
WSSV is considered to be the most devastating viral disease affecting
the shrimp industry around the world. This disease has caused huge
production losses to most of the shrimp producing countries of the world
(Nakano et al., 1994; Chou et al., 1995; Huang et al., 1995; Wang et al., 1995;
Wongteerasupaya et al., 1995; Flegel, 1997; Lu et al., 1997; Lo et al., 2003).
Although extensive research and considerable progress has been made in the
characterization of WSSV, little work has been done on the host immune
response at the molecular and cellular level particularly by haemocytes in
response to the viral infection (Soderhall and Cerenius, 1992; Wongpanya et
al., 2007). Also, little is known about the molecular mechanisms underlying
the WSSV infection and host immune response. Therefore, there is an urgent
need to understand the molecular basis of WSSV pathogenesis in shrimp,
which may be helpful in developing strategies for management of the
disease and for long-term sustainability of penaeid shrimp farming
worldwide.
Crustacean response to viral infection may share some of the same
pathways in the innate immune system already explored for defense against
Molecular Characterization and Gene Expression Profiling of Antimicrobial Peptides in Penaeid Shrimps
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