| 摘要 |
<p>Isolated DNA from Penaeus vannamei was digested with restriction enzymes, restriction fragments of genomic DNA inserted into a plasmid vector and screened for recombinant plasmids containing repeated sequences. Ten of the resulting isolates contained representatives of the same repeated element, a satellite sequence present in one or more blocks of tandemly repeated units. The cloned repeat units range in size from about 100 to 200 base pairs, more typically between about 139 to 188 base pairs. Embedded within each cloned repeat unit are 6 to 15 copies of a tandemly repeated pentanucleotide microsatellite. The genome of P. vannamei contains approximately one million copies of this satellite/microsatellite unit. The sequences are useful as markers for the selection of shrimp having a genetically-transmitted favorable growth characteristic, such as increased reproduction, enhanced growth rate, increased size, disease-resistance, and the ability to grow in colder waters, for improved aquacultured shrimp production. Hybridization of the marker to an isolated Peaneus shrimp mucleic acid molecule can be used to identify species, strains or individual shrimp having the desired characteristics. Once identified, these shrimps can be bred to shrimp having the same or an additional desired characteristic to produce a high quality, genetically superior seedstock or larvae useful for the economic production of farmed shrimp.</p> |
