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Other innate immunity components in fish mucusThere are also a few important components of fish epidermal mucus which play an important role in innate immunity of fishes such as C-reactive proteins (CRPs), transferrin, ALP, complement proteins, etc. CRPs belong to a family of multifunctional proteins (pentraxins) and are capable of binding various ligands in a Ca2+ dependent binding affinity. Th..

Antimicrobial peptidesAntimicrobial peptides are increasingly recognized as a critical factor in host defence mechanism and found in organisms ranging from microbes, plants to animal species (Fernandes et al., 2004; Kennedy et al., 2009). It also plays an important role in fish when compared with mammals as fish rely more on their innate immune system (Hancock, 1997; Hancock and Scott, 2000). Fi..

Role of skin mucus components in innate immunityThe major function of the mucus appears to provide the effective separation between internal and external environment of fish, abrasion resistance and primary defense against the numerous aquatic pathogens by virtue of its components which include proteases, AMPs, lysozyme, CRP. These are discussed in detail below. ProteasesProtease refers to a gro..

IntroductionThe aquaculture industries with high densities of fishes are susceptible to diseases caused by many pathogens. Fish possess numerous distinct and complex defense mechanisms to protect themselves from these pathogenic infections amongst which fish skin mucus acts as the first line of physical defense against pathogens (Wang et al., 2011). The fish skin mucus provides a stable physical..

RECOMBINEERING INCREASES THE SPEED OF GENE CLONINGAssembling new DNA vectors with different genes of interest can become difficult when the gene is long, since it can be hard to identify unique restriction enzymes compatible with a polylinker that do not cut within the gene. Large recombinant DNA vectors can be created using homologous recombination, a process called recombineering (Fig. 3.25). ..

FEATURES OF EXPRESSION VECTORSBecause foreign protein can be toxic to E. coli, especially if made in large amounts, the promoter used to express the foreign gene is critical.  critical 대단히 중요한 If too much foreign protein is made, the host cell may die. To control protein production, expression vectors have promoters with on/off switches; therefore, the host cell is allowed to grow and then after..

EUKARYOTIC EXPRESSION LIBRARIESIn expression libraries, the vector has sequences required for transcription and translation of the insert. This means that the insert DNA is expressed as RNA and then translated into a protein. An expression library, in essence, generates a protein from every cloned insert, whether it is a real gene or not.  When eukaryotic DNA is studied, expression libraries are..

SCREENING THE LIBRARY OF GENES BY HYBRIDIZATIONOnce the library is assembled, researchers often want to identify a particular gene or segment of DNA within the library. Sometimes the gene of interest is similar to one from another organism. Sometimes the gene of interest contains a particular sequence. For example, many enzymes use ATP to provide energy. Enzymes that bind ATP share a common sign..

GETTING CLONED GENES INTO BACTERIA BY TRANSFORMATIONOnce the gene of interest is cloned into a vector, the construct can be put back into a bacterial cell through a process called transformation (Fig. 3.18) (see Box 3.2).FIGURE 3.18 Transformation Bacterial cells are able to take up DNA such as recombinant plasmids by incubation with metal ions such as Ca++ on ice. This destabilizes the bacteria..

SPECIFIC TYPES OF CLONING VECTORS Because E. coli is the main host organism used for manipulating DNA, most vectors are based on plasmids or viruses that can survive in E. coli or similar bacteria. Most vectors have bacterial origins of replication and antibiotic resistance genes.  The polylinker or multiple cloning site is usually placed between prokaryotic promoter and terminator sequences (Fi..