Functional dissection of the Suppressor of UnderReplication protein of Drosophila melanogaster: identification of domains influencing chromosome binding and DNA replication.
The Suppressor of UnderReplication (SuUR) gene controls the DNA underreplication in intercalary and pericentric heterochromatin of Drosophila melanogaster salivary gland polytene chromosomes. In the present work, we investigate the functional importance of different regions of the SUUR protein by expressing truncations of the protein in an UAS-GAL4 system. We find that SUUR has at least two separate chromosome-binding regions that are able to recognize intercalary and pericentric heterochromatin specifically. The C-terminal part controls DNA underreplication in intercalary heterochromatin and partially in pericentric heterochromatin regions. The C-terminal half of SUUR suppresses endoreplication when ectopically expressed in the salivary gland. Ectopic expression of the N-terminal fragments of SUUR depletes endogenous SUUR from polytene chromosomes, causes the SuUR- phenotype and induces specific swellings in heterochromatin.
Kolesnikova
T D
TD
Laboratory of Molecular Cytogenetics, Institute of Cytology and Genetics SB RAS, Lavrentyev Ave. 10, 630090 Novosibirsk, Russia.
Makunin
I V
IV
Volkova
E I
EI
Pirrotta
V
V
Belyaeva
E S
ES
Zhimulev
I F
IF
D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D002875:Chromosomes / Q000378:metabolism*; D004247:DNA / Q000235:genetics; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D029721:Drosophila Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics* / Q000378:metabolism*; D005260:Female; D017344:Genes, Insect; D006570:Heterochromatin / Q000378:metabolism; D008297:Male; D009154:Mutation; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012469:Salivary Glands / Q000378:metabolism
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D006570:Heterochromatin; D011993:Recombinant Fusion Proteins; C464850:SuUR protein, Drosophila; D004247:DNA