The Drosophila Suppressor of Underreplication Protein Binds to Late-Replicating Regions of Polytene Chromosomes

• Published in: Genetics (Austin) Vol. 160; no. 3; pp. 1023 - 1034
• Main Authors: Makunin, I. V, Volkova, E. I, Belyaeva, E. S, Nabirochkina, E. N, Pirrotta, V, Zhimulev, I. F
• Format: Journal Article
• Language: English
• Published: United States Genetics Soc America 01-03-2002; Genetics Society of America
• Subjects: Amino Acid Sequence; Animals; Base Sequence; Chromosome Mapping; Chromosomes - genetics; Chromosomes - metabolism; DNA-Binding Proteins - genetics; DNA-Binding Proteins - immunology; DNA-Binding Proteins - metabolism; Drosophila; Drosophila - genetics; Drosophila Proteins - genetics; Drosophila Proteins - immunology; Drosophila Proteins - metabolism; Genes; Insects; Molecular Sequence Data; Polyploidy; Promoter Regions, Genetic; Proteins; Sequence Alignment; Sequence Analysis, DNA; SuUR gene
• ISSN: 0016-6731; 1943-2631; 1943-2631
• DOI: 10.1093/genetics/160.3.1023

In many late-replicating euchromatic regions of salivary gland polytene chromosomes, DNA is underrepresented. A mutation in the SuUR gene suppresses underreplication and leads to normal levels of DNA polytenization in these regions. We identified the SuUR gene and determined its structure. In the SuUR mutant stock a 6-kb insertion was found in the fourth exon of the gene. A single SuUR transcript is present at all stages of Drosophila development and is most abundant in adult females and embryos. The SuUR gene encodes a protein of 962 amino acids whose putative sequence is similar to the N-terminal part of SNF2/SWI2 proteins. Staining of salivary gland polytene chromosomes with antibodies directed against the SuUR protein shows that the protein is localized mainly in late-replicating regions and in regions of intercalary and pericentric heterochromatin.