The dosage compensation regulators MLE, MSL-1 and MSL-2 are interdependent since early embryogenesis in Drosophila.
We have analyzed the expression pattern and localization of MLE, MLS-1, MSL-2, and histone H4Ac16 during embryogenesis to determine when msl-dependent dosage compensation begins. Maternal MSL-1 and MLE are present in both sexes at fertilization. MSL-2 lacks a maternal component, and male-specific zygotic expression is detectable at the end of blastoderm. During germ band extension, MSL-1, MSL-2, MLE, and histone H4Ac16 display coincident sub-nuclear localization in male embryos. In embryos lacking one of the MSL proteins, the sub-nuclear localization of the other MSLs and of histone H4Ac16 is not detected. We conclude that the MSL proteins associate with the X chromosome and are interdependent since early embryogenesis.
Rastelli
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Howard Hughes Medical Institute, Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030, USA.
Richman
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Kuroda
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MI
D000818:Animals; D002467:Cell Nucleus / Q000737:chemistry; D002868:Chromosomal Proteins, Non-Histone; D004265:DNA Helicases; D004268:DNA-Binding Proteins; D004303:Dosage Compensation, Genetic; D004330:Drosophila / Q000196:embryology / Q000235:genetics*; D029721:Drosophila Proteins; D004625:Embryo, Nonmammalian / Q000502:physiology; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D005854:Germ Cells / Q000502:physiology; D006657:Histones / Q000502:physiology; D007301:Insect Hormones / Q000502:physiology; D008297:Male; D009687:Nuclear Proteins / Q000032:analysis / Q000502:physiology*; D012727:Sex Characteristics; D013347:Subcellular Fractions / Q000737:chemistry; D014157:Transcription Factors / Q000502:physiology
D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D006657:Histones; D007301:Insect Hormones; D009687:Nuclear Proteins; D014157:Transcription Factors; C070837:mle protein, Drosophila; C082132:msl-1 protein, Drosophila; C094166:msl-2 protein, Drosophila; D004265:DNA Helicases