SET1A/COMPASS and shadow enhancers in the regulation of homeotic gene expression

The Polycomblike gene of Drosophila melanogaster, a member of the Polycomb Group of genes, is required for the correct spatial expression of the homeotic genes of the Antennapaedia and Bithorax Complexes. Mutations in Polycomb Group genes result in ectopic homeotic gene expression, indicating that Polycomb Group proteins maintain the transcriptional repression of specific homeotic genes in specific tissues during development. We report here the isolation and molecular characterisation of the Polycomblike gene. The Polycomblike transcript encodes an 857 amino acid protein with no significant homology to other proteins. Antibodies raised against the product of this open reading frame were used to show that the Polycomblike protein is found in all nuclei during embryonic development. Antibody staining also revealed that the Polycomblike protein is found on larval salivary gland polytene chromosomes at about 100 specific loci, the same loci to which the Polycomb and polyhomeotic proteins, two other Polycomb Group proteins, are found. These data add further support for a model in which Polycomb Group proteins form multimeric protein complexes at specific chromosomal loci to repress transcription at those loci.

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Decision letter: Deregulated FGF and homeotic gene expression underlies cerebellar vermis hypoplasia in CHARGE syndrome

10.7554/elife.01305.011 ◽

2013 ◽

Keyword(s):

Gene Expression ◽

Charge Syndrome ◽

Cerebellar Vermis ◽

Homeotic Gene ◽

Homeotic Gene Expression

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Faculty Opinions recommendation of A long noncoding RNA maintains active chromatin to coordinate homeotic gene expression.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.9550956.10966054 ◽

2011 ◽

Author(s):

Leonie Ringrose

Keyword(s):

Gene Expression ◽

Long Noncoding Rna ◽

Noncoding Rna ◽

Homeotic Gene ◽

Active Chromatin ◽

Homeotic Gene Expression

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Trithorax regulates multiple homeotic genes in the bithorax and Antennapedia complexes and exerts different tissue-specific, parasegment-specific and promoter-specific effects on each

Development ◽

10.1242/dev.117.1.119 ◽

1993 ◽

Vol 117 (1) ◽

pp. 119-134 ◽

Cited By ~ 16

Author(s):

T.R. Breen ◽

P.J. Harte

Keyword(s):

Gene Expression ◽

Expression Patterns ◽

The Body ◽

Homeotic Gene ◽

Homeotic Genes ◽

Sex Combs Reduced ◽

Tissue Specific ◽

Specific Effects ◽

Normal Expression ◽

Homeotic Gene Expression

The trithorax (trx) gene is required for normal development of the body plan in Drosophila embryos and adults. Mutations in trx cause homeotic transformations throughout the body. Genetic studies suggest that trx encodes a positive regulatory factor required throughout development for normal expression of multiple homeotic genes of the bithorax and Antennapedia complexes (BX-C and ANT-C). To determine how trx influences homeotic gene expression, we examined the expression of the BX-C genes Ultrabithorax, abdominal-A, Abdominal-B and the ANT-C genes Antennapedia, Sex combs reduced and Deformed in trx embryos. We show that trx does indeed exert its effects by positively regulating homeotic gene expression and that its effects on expression of individual homeotic genes are complex: each of the BX-C and ANT-C genes examined exhibits different tissue-specific, parasegment-specific and promoter-specific reductions in their expression. This implies that each of these genes have different requirements for trx in different spatial contexts in order to achieve normal expression levels, presumably depending on the promoters involved and the other regulatory factors bound at each of their multiple tissue- and parasegment-specific cis-regulatory sites in different regions of the embryo. These results also imply that those components of homeotic gene expression patterns for which trx is dispensable, require other factors, possibly those encoded by other trithorax-like genes.

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Blocking cell division does not remove the requirement for Polycomb function in Drosophila embryogenesis

Development ◽

10.1242/dev.110.4.1319 ◽

1990 ◽

Vol 110 (4) ◽

pp. 1319-1325 ◽

Cited By ~ 4

Author(s):

A.P. Gould ◽

R.Y. Lai ◽

M.J. Green ◽

R.A. White

Keyword(s):

Gene Expression ◽

Cell Division ◽

Dna Replication ◽

Ectopic Expression ◽

Homeotic Gene ◽

Germ Band ◽

Drosophila Embryogenesis ◽

Stable Transmission ◽

Homeotic Gene Expression

The Polycomb (Pc) gene is required from the extended germ band stage onwards, to maintain spatially restricted patterns of homeotic gene expression. It has been thought to be involved in the ‘stable inheritance of the determined state’. In this paper, we have tested the notion that the Pc gene is required specifically during or after DNA replication to enable the stable transmission of states of gene activity. We found that arresting cell division using the string mutation or blocking DNA replication with aphidicolin failed to prevent ectopic expression of the homeotic gene Ultrabithorax in Pc mutants. Thus, even in the absence of DNA replication, Pc is required to maintain spatially restricted patterns of homeotic gene expression. The role of the Pc gene product in the stable repression of homeotic gene transcription is discussed.

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SEUSS, a member of a novel family of plant regulatory proteins, represses floral homeotic gene expression withLEUNIG

Development ◽

10.1242/dev.129.1.253 ◽

2002 ◽

Vol 129 (1) ◽

pp. 253-263 ◽

Cited By ~ 7

Author(s):

Robert G. Franks ◽

Chunxin Wang ◽

Joshua Z. Levin ◽

Zhongchi Liu

Keyword(s):

Gene Expression ◽

Floral Meristem ◽

Genetic Identification ◽

Homeotic Gene ◽

Dimerization Domain ◽

Homeotic Transformation ◽

Floral Organs ◽

Floral Homeotic Gene ◽

Homeotic Gene Expression ◽

Floral Homeotic

Proper regulation of homeotic gene expression is critical for pattern formation during both animal and plant development. A negative regulatory mechanism ensures that the floral homeotic gene AGAMOUS is only expressed in the center of an Arabidopsis floral meristem to specify stamen and carpel identity and to repress further proliferation of the floral meristem. We report the genetic identification and characterization of a novel gene, SEUSS, that is required in the negative regulation of AGAMOUS. Mutations in SEUSS cause ectopic and precocious expression of AGAMOUS mRNA, leading to partial homeotic transformation of floral organs in the outer two whorls. The effects of seuss mutations are most striking when combined with mutations in LEUNIG, a previously identified repressor of AGAMOUS. More complete homeotic transformation of floral organs and a greater extent of organ loss in all floral whorls were observed in the seuss leunig double mutants. By in situ hybridization and double and triple mutant analyses, we showed that this enhanced defect was caused by an enhanced ectopic and precocious expression of AGAMOUS. Using a map-based approach, we isolated the SEUSS gene and showed that it encodes a novel protein with at least two glutamine-rich domains and a highly conserved domain that shares sequence identity with the dimerization domain of the LIM-domain-binding transcription co-regulators in animals. Based on these molecular and genetic analyses, we propose that SEUSS encodes a regulator of AGAMOUS and functions together with LEUNIG.

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