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Updated: Aug 11, 2026
10:07
Isolation of Giant Lampbrush Chromosomes from Living Oocytes of Frogs and Salamanders
Published on: December 5, 2016
Hierarchical order in a satellite DNA from the European brown frog Rana dalmatina
D E Cardone1, I Feliciello, G Chinali
1Dipartimento di Medicina Clinica e Sperimentale, Facoltà di Medicine e Chirurgia, Università di Napoli Federico II.
Summary
Researchers identified a novel satellite DNA sequence, RdS2, in the European brown frog Rana dalmatina. This species-specific repetitive DNA exhibits a hierarchical structure, similar to other satellite DNAs found across various genomes.
Area of Science:
- Genomics
- Molecular Biology
- Evolutionary Biology
Background:
- Repetitive DNA elements, such as satellite DNA, play crucial roles in genome structure and evolution.
- Understanding the organization and characteristics of satellite DNA is essential for deciphering genome complexity.
Purpose of the Study:
- To clone and sequence a repetitive DNA fragment from the European brown frog Rana dalmatina.
- To characterize the structure and abundance of this satellite DNA, named RdS2.
- To investigate the presence of higher-order repeat structures within the RdS2 sequence.
Main Methods:
- DNA cloning and sequencing of an EcoRV fragment.
- Analysis of tandem repeat units within the cloned fragment.
- Southern blot hybridization to assess repeat copy number and higher-order structures.
Main Results:
- A 341 bp EcoRV fragment containing 11 tandem copies of a 31 bp satellite DNA repeat (RdS2) was identified.
- RdS2 is species-specific to Rana dalmatina, not A+T rich, and constitutes approximately 0.24% of the genome.
- Southern blot analysis revealed high-order repeats with periodicities of 10–26 unit repeats, indicating a hierarchical organization.
Conclusions:
- The satellite DNA RdS2 in Rana dalmatina exhibits a hierarchical repeat structure, comparable to satellite DNAs in other species.
- RdS2 represents a significant component of the Rana dalmatina genome and provides insights into repetitive DNA evolution.
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