PMID- 7623836
OWN - NLM
STAT- MEDLINE
DCOM- 19950829
LR  - 20210526
IS  - 0270-7306 (Print)
IS  - 1098-5549 (Electronic)
IS  - 0270-7306 (Linking)
VI  - 15
IP  - 8
DP  - 1995 Aug
TI  - scute (sis-b) function in Drosophila sex determination.
PG  - 4430-40
AB  - The primary sex determination signal, the X chromosome-to-autosome (X/A) ratio, 
      controls the choice of sexual identity in the Drosophila melanogaster embryo by 
      regulating the activity of the early promoter of the Sex-lethal gene, Sxl-Pe. 
      This promoter is activated in females (2X/2A), while it remains off in males 
      (1X/2A). Promoter activation in females is dependent upon X-linked numerator 
      genes. One of these genes, sisterless-b (sis-b), corresponds to the scute (sc) 
      locus of the achaete-scute complex, and it encodes a helix-loop-helix 
      transcription factor. In the studies reported here we have used monoclonal 
      antibodies to study the expression and functioning of the sc(sis-b) protein. Sc 
      is first detected at nuclear cycle 6 to 7, well before Sxl-Pe is first active. At 
      this stage, the protein is in the cytoplasm, not the nucleus. Only after the 
      formation of the syncytial blastoderm, at nuclear cycle 10 to 11, does a 
      substantial fraction of the protein enter the nucleus, and this nuclear import 
      closely coincides with the initial activation of Sxl-Pe. Consistent with the idea 
      that the dose of sc(sis-b) is critical for its function as an X-chromosome 
      counting element, wild-type syncytial blastoderm embryos could be grouped into 
      two classes based on the level of protein. Western blot (immunoblot) analysis 
      demonstrates that this difference in protein level correlates directly with the 
      activity state of the Sxl gene. Finally, we provide the first direct evidence 
      that Sc forms heteromeric complexes in vivo in early embryos with the maternally 
      derived helix-loop-helix protein Daughterless. This in vivo complex is likely to 
      be critical for Sc function in Sxl-Pe activation.
FAU - Deshpande, G
AU  - Deshpande G
AD  - Department of Molecular Biology, Princeton University, New Jersey 08544, USA.
FAU - Stukey, J
AU  - Stukey J
FAU - Schedl, P
AU  - Schedl P
LA  - eng
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Mol Cell Biol
JT  - Molecular and cellular biology
JID - 8109087
RN  - 0 (Antibodies, Monoclonal)
RN  - 0 (Basic Helix-Loop-Helix Transcription Factors)
RN  - 0 (DNA-Binding Proteins)
RN  - 0 (Da protein, Drosophila)
RN  - 0 (Drosophila Proteins)
RN  - 0 (Nuclear Proteins)
RN  - 0 (Transcription Factors)
RN  - 0 (sc protein, Drosophila)
SB  - IM
GS  - sis-b
MH  - Animals
MH  - Antibodies, Monoclonal
MH  - Antibody Specificity
MH  - Basic Helix-Loop-Helix Transcription Factors
MH  - Biological Transport
MH  - Blastoderm
MH  - Blotting, Western
MH  - Cell Compartmentation
MH  - Cell Nucleus/metabolism
MH  - DNA-Binding Proteins/*biosynthesis/genetics/immunology/metabolism
MH  - *Drosophila Proteins
MH  - Drosophila melanogaster/*embryology/genetics
MH  - Female
MH  - Gene Dosage
MH  - *Gene Expression Regulation, Developmental
MH  - Hot Temperature
MH  - Immunohistochemistry
MH  - Male
MH  - Nuclear Proteins/metabolism
MH  - Protein Binding
MH  - Sex Differentiation/*physiology
MH  - Time Factors
MH  - Tissue Distribution
MH  - Transcription Factors/*biosynthesis/genetics/immunology/metabolism
MH  - X Chromosome
PMC - PMC230683
EDAT- 1995/08/01 00:00
MHDA- 1995/08/01 00:01
PMCR- 1995/08/01
CRDT- 1995/08/01 00:00
PHST- 1995/08/01 00:00 [pubmed]
PHST- 1995/08/01 00:01 [medline]
PHST- 1995/08/01 00:00 [entrez]
PHST- 1995/08/01 00:00 [pmc-release]
AID - 10.1128/MCB.15.8.4430 [doi]
PST - ppublish
SO  - Mol Cell Biol. 1995 Aug;15(8):4430-40. doi: 10.1128/MCB.15.8.4430.