Molecular Characterization and Gene Expression Profiling ... - CUSAT

Chapter 4
Temporal regulatory genes of WSSV (Liu et al., 2005), epidemics of WSSV
(Wu et al., 2001) various host species of WSSV (Jiravanichpaisal et al., 2001;
Rodriguez et al., 2003) WSSV pathology (Wang et al., 1995, 2002; Lightner
1996), WSSV transmission (Chang et al., 1996; Lightner et al., 1997)
diagnostic methods for WSSV (Liu et al., 2002; Okumura et al., 2004) and
control of WSSV (Dupuy et al., 2004; Park et al., 2004; Witteveldt et al.,
2004b).
Although considerable progress has been made in the characterization
of WSSV, little work has been done on the host immune response
particularly by haemocytes in response to the viral infection at the molecular
level (Soderhall and Cerenius, 1992; Wongpanya et al., 2007). Also, little is
known about the molecular mechanisms underlying the WSSV infection and
host immune response. To develop effective infection controls, more
information about the mode of infection and interaction between the virus
and its host is needed. Knowledge of the immune system in shrimp is
necessary to develop methods to control and minimize the loss of production
due to infectious diseases. Larger numbers of immune-related genes need to
be identified and functionally characterized to better understand shrimp
immunity.
4.1.1. Antiviral immune response
The molecular mechanisms that underlie the crustacean antiviral
immune responses are still unknown and only in the early stages of
investigation. Recently, studies using different techniques have been carried
out on host-WSSV interactions in crustaceans (Lan et al., 2006; Liu et al.,
2006; Wang et al., 2006a, 2007b; Zhao et al., 2007). It has been reported that
virus-inhibiting proteins could be produced and some genes were up-
regulated upon viral infection in crustaceans (Pan et al,. 2000; Rojtinnakorn
et al., 2002; Roux et al., 2002; Dhar et al., 2003; He et al., 2005; Pan et al., 2005).
Genes induced by viral infections and genes whose expression is associated
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