Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

Molecular Characterization of Salt Regulatory Genes in Oreochromis Niloticus and Oreochromis Mossambicus

SONYA MRONG
Department of Fisheries Biology & Genetics Bangladesh Agricultural University, Mymensingh 2202, Bangladesh

BHAKTA SUPRATIM SARKER
Department of Fisheries Biology & Genetics Bangladesh Agricultural University, Mymensingh 2202, Bangladesh

MD. SADIQUL ISLAM
Department of Fisheries Biology & Genetics Bangladesh Agricultural University, Mymensingh 2202, Bangladesh

MD. MONIRUL ISLAM
Biotechnology Division, Bangladesh Institute of Nuclear Agriculture, Mymensingh, Bangladesh

MD. SAMSUL ALAM
Department of Fisheries Biology & Genetics Bangladesh Agricultural University, Mymensingh, 2202, Bangladesh

Abstract/ Executive Summary:

Polymorphisms in microsatellite DNA loci located in the salt regulatory genes have been found to show variations in salinity tolerance and growth in fish. Five microsatellite loci located in the salt regulatory genes prolactin 1 (Prl1), transferrin-A (TFA) and transferrin-B (TFB)have been characterized in Oreochromis niloticus and O. mossambicus. The microsatellite markers were amplified from a total of 78 fish by polymerase chain reaction and genotyped by polyacrylamide and agarose gel electrophoresis. The Prl1 (L-K), PrlI-MS01, TFA and TFB loci in O. niloticus and Prl I-MS01, TFA lociinO. mossambicus were found to be polymorphic. The average observed (Ho) and expected heterozygosity (He) values in O. niloticus were higher than the values in O. mossambicus. Except locus Prl1(L-K) in O. niloticus, the FIS values were negative in all other cases which indicates that both the two populations (O. niloticus and O. mossambicus) had excess of heterozygosity. The loci Prl I-MS01 and TFA were both in O. mossambicus and O. niloticusand Prl1 (L-K) in O. niloticus were found to be significantlydeviated from Hardy-Weinberg expectations. Polymorphisms detected in four loci in O. niloticus can be used for studying association of polymorphisms with salt tolerance and selection of salt tolerant individuals of this species through marker assisted selection.

Keywords: Salt tolerance, Polymorphisms, Tilapia, Molecular breeding

Location: Khulna and Mymensingh districts of Bangladesh

Start Date:

End Date:

Program Area: Variety and Species

Commodity: Tilapia

Objectives:

The objective of the present study was to characterize the microsatellite loci located in the salt regulatory genes Prl1, TFA and TFB of O. niloticus and O. mossambicus.

Methodology:

Experimental fish: A total of 78 tilapia including 45 Mozambique tilapia, O. mossambicus and 33 Nile tilapia, O. niloticus were collected from Khulna and Mymensingh districts of Bangladesh, respectively, tagged with Passive Integrative Tags (PIT) and stocked in cemented cisterns. Tissue samples were collected from caudal fin and immediately preserved in separate microfuge tubes containing 95% ethanol and stored at -20^oC. DNA extraction and PCR amplification: Genomic DNA was extracted from the collected fin tissues according to the method described by Islam and Alam (2004). The DNA samples were quantitated using a spectrophotometer (Biophotometer plus Eppendorf, Germany)and adjusted to a final concentration 50 ng/μl.The 20 μl PCR reactions contained 2 μl 10X PCR buffer, 1.6 μldNTPs (2.5mM each), 2 μl(1μM) of forward and reverse primers (Table I), and 1 unit of Taq DNA polymerase (Takara, Japan), and 2 μl (100 ng) template DNA. The thermal profile of the PCR wasas follows: For Prl1(S-K), TFA and TFB- initial denaturation at 95^oC for 3 min, 35 cycles comprising denaturation at 95^oC for 30 s, annealing at 60oC for 30 s, and extension at 72^oC for 1 min, followed by a by a final extension step at 72^oC for 7 min; for Prl1(L-K), Prl IMS01: initial denaturation at 95^oC for 3 min, 35 cycles of 95^oC for 30 s, 53^oC for 30 s, 72^oC for 1 min, and a final extension at 72^oC for 7 min. The PCR products of Prl1(S-K), TFA and TFB were separated by polyacrylamide gel electrophoresis while those of Prl1(L-K) and Prl I-MS01 were separated by 3% agarose gel electrophoresis. The primer sequences along with the annealing temperature are shown. Microsatellite data analysis: The bands representing particular alleles at the microsatellite loci were scored by using AlphaEaseFC version 4.0 software from the gel image and the sizes of the bands/alleles were determined with respect to the 100bp DNA marker. The software GenAlEx version 6.503 (Peakall and Smouse 2012) was used to analyze the allelic variation and conformity to Hardy-Weinberg expectationof microsatellite markers in the samples of two tilapia species.

Source of Information: Bangladesh J. Fish. (2019) 31(2) : 181-188

Article Link (Online Journal):

Funding Source:

1.

Budget:

Total Budget (Tk.) :

Achievement/Findings:

In conclusion, we have detected polymorphism in three microsatellite loci of the salt regulatory genes prolactin and transferrin in O. niloticus and two loci in O. mossambicus through our preliminary investigation. The fishes carrying different alleles in the salt regulatory genes will allow to select salt tolerant fish. The fish have already been PIT tagged so they can be grouped according to their genotypes and reared in different salinity to see which genotypes tolerate salinity levels better than the others. Thus a stock of salinity tolerant O. niloticus can be developed through marker assisted selection.

Knowledge Management: Journal