Characterization of two novel gadd45a genes in hybrid tilapia and their responses to the infection of Streptococcus agalactiae.
Diseases are one of the major challenges in tilapia aquaculture. Identification of DNA markers associated with disease resistance may facilitate the acceleration of the selection for disease resistance. Gadd45a (growth arrest and DNA damage 45 A), a stress-inducible gene in humans and mice, has not been studied in fish. We characterized the two prologues of Gadd45a genes in hybrid tilapia. Gadd45a1 and Gadd45a2 shared an identical gene structure and showed an amino acid sequence identity of 73.8%. Their expressions were detected in all 10 tissues examined, with the kidney and gill having high transcriptional expressions. The expression levels of Gadd45a1 were significantly lower than those of Gadd45a2 in all examined tissues. After a challenge with a bacterial pathogen Streptococcus agalactiae, the expressions of the two genes were up-regulated significantly in the spleen, kidney, liver and intestine. These findings suggest that the two Gadd45a genes play an important role in the resistance to S. agalactiae in tilapia. We identified 10 SNPs in the two genes. The SNP markers in the two Gadd45a genes could be used to examine whether they are associated with resistance to S. agalactiae.
Molecular Population Genetics Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore; Key Laboratory of Freshwater Fishery Germplasm Resources, Ministry of Agriculture, Shanghai Ocean University, Shanghai 201306, China.
Yubang
Y
Shen
Molecular Population Genetics Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore.
Keyi
K
Ma
Molecular Population Genetics Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore.
Feng
F
Liu
Molecular Population Genetics Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore; Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Republic of Singapore; School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore. Electronic address: genhua@tll.org.sg.
Gen Hua
GH
Yue
D000818:Animals; D017756:Aquaculture; D023681:Cichlids / Q000235:genetics; D005393:Fish Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000276:immunology; D006824:Hybridization, Genetic; D007113:Immunity, Innate; D047908:Intracellular Signaling Peptides and Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D020641:Polymorphism, Single Nucleotide; D020539:Sequence Analysis, Protein / Q000662:veterinary; D013290:Streptococcal Infections / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D013292:Streptococcus agalactiae / Q000502:physiology; D017210:Tilapia; D000097642:GADD45 Proteins
D029941:Fish Proteins; D047908:Intracellular Signaling Peptides and Proteins; D000097642:GADD45 Proteins
Gadd45a; SNP; Streptococcus agalactiae; Tilapia