Species-specific repeat units in the intergenic spacer of the ribosomal RNA cistron of Anopheles aquasalis Curry

• Published in: The American journal of tropical medicine and hygiene Vol. 59; no. 5; p. 673
• Main Authors: Perera, O P, Cockburn, A F, Mitchell, S E, Conn, J, Seawright, J A
• Format: Journal Article
• Language: English
• Published: United States 01-11-1998
• Subjects: Animals; Anopheles - classification; Anopheles - genetics; Anopheles - parasitology; Base Sequence; DNA Probes - genetics; DNA, Ribosomal - genetics; Female; Genes - genetics; Genomic Library; Insect Vectors - classification; Insect Vectors - genetics; Insect Vectors - parasitology; Malaria - transmission; Molecular Sequence Data; Repetitive Sequences, Nucleic Acid; RNA, Ribosomal - genetics; RNA, Ribosomal, 28S - genetics; Sequence Homology, Nucleic Acid; South America; Species Specificity; South America
• ISSN: 0002-9637
• DOI: 10.4269/ajtmh.1998.59.673

A genomic DNA library of Anopheles aquasalis Curry was screened for clones that hybridized more intensely to DNA from A. aquasalis than to DNA from A. benarrochi Gabaldon, Cova Garcia, and Lopez, A. konderi Galvao and Damasceno, A. nuneztovari Gabaldon cytotypes A, B, and C, A. oswaldoi (Peryassu), A. rangeli Gabaldon, Cova Garcia, and Lopez, or A. trinkae Faran. Two specific clones (2.5 kilobasepairs [kbp] and 3.0 kbp) from A. aquasalis were isolated. Both A. aquasalis-specific clones were from the intergenic spacer region of the ribosomal RNA (rRNA) cistron. Upon digestion with Rsa I, a 900-bp fragment from the clone AA-1 hybridized specifically to A. aquasalis DNA. Analysis of the DNA sequence of this fragment revealed four tandemly repeated 36-bp units. Three of these repeat units were identical, and the fourth was 94% identical to the others. The DNA sequence of a highly conserved region of these repeats was used to synthesize an oligonucleotide probe specific to A. aquasalis.