Published in PLoS Genetics
Polycomb and trithorax group proteins regulate cellular pluripotency and differentiation by maintaining hereditable states of transcription. Many Polycomb and trithorax group proteins have been implicated in the covalent modification or remodeling of chromatin, but how they interact with each other and the general transcription machinery to regulat...
Published in Genes & Development
Published in Development
Members of the Polycomb group of repressors and trithorax group of activators maintain heritable states of transcription by modifying nucleosomal histones or remodeling chromatin. Although tremendous progress has been made toward defining the biochemical activities of Polycomb and trithorax group proteins, much remains to be learned about how they ...
Published in Development
The Drosophila kismet gene was identified in a screen for dominant suppressors of Polycomb, a repressor of homeotic genes. Here we show that kismet mutations suppress the Polycomb mutant phenotype by blocking the ectopic transcription of homeotic genes. Loss of zygotic kismet function causes homeotic transformations similar to those associated with...
Published in Current Opinion in Genetics & Development
The differential transcription of Drosophila homeotic genes is maintained by the Polycomb and trithorax groups of regulatory proteins, many of which are thought to modulate chromatin structure. During the past year, studies of a trithorax group member, brahma, and related yeast and human proteins have suggested that they are components of huge comp...
Published in Developmental Cell
Histone H1 variants play key roles in the regulation of higher-order chromatin structure and have been implicated in numerous developmental processes. In this issue of Developmental Cell, Pérez-Montero et al. (2013) present evidence that the Drosophila histone H1 variant dBigH1 prevents premature activation of the zygotic genome during early embryo...
Published in Genetics
In this report, we investigate the mechanisms that regulate Drosophila histone H1 expression and its association with chromatin in vivo. We show that histone H1 is subject to negative autoregulation and exploit this result to examine the effects of mutations of the main phosphorylation site of histone H1.
Published in PLoS Genetics
dMi-2 is a highly conserved ATP-dependent chromatin-remodeling factor that regulates transcription and cell fates by altering the structure or positioning of nucleosomes. Here we report an unanticipated role for dMi-2 in the regulation of higher-order chromatin structure in Drosophila. Loss of dMi-2 function causes salivary gland polytene chromosom...
Published in Genetics
The Drosophila brahma (brm) gene encodes an activator of homeotic genes related to the yeast chromatin remodeling factor SWI2/SNF2. Here, we report the phenotype of null and dominant-negative brm mutations. Using mosaic analysis, we found that the complete loss of brm function decreases cell viability and causes defects in the peripheral nervous sy...
Published in Proceedings of the National Academy of Sciences
We have identified a Drosophila gene (arflike, arl) encoding a protein that is structurally related (approximately 55% identity) to the ADP-ribosylation factors (ARFs) of yeast and mammals. Biochemical analyses of purified recombinant arl-encoded protein revealed properties similar to the ARF proteins, including the ability to bind and hydrolyze GT...
Published in Proceedings of the National Academy of Sciences
The Drosophila trithorax group gene brahma (brm) encodes the ATPase subunit of a SWI/SNF-like chromatin-remodeling complex. A key question about chromatin-remodeling complexes is how they interact with DNA, particularly in the large genomes of higher eukaryotes. Here, we report the characterization of BAP111, a BRM-associated protein that contains ...
Published in Developmental Cell
Histone H1 variants play key roles in the regulation of higher-order chromatin structure and have been implicated in numerous developmental processes. In this issue of Developmental Cell, Pérez-Montero et al. (2013) present evidence that the Drosophila histone H1 variant dBigH1 prevents premature activation of the zygotic genome during early embryo...
Published in The EMBO Journal
Drosophila brahma (brm) encodes the ATPase subunit of a 2 MDa complex that is related to yeast SWI/SNF and other chromatin-remodeling complexes. BRM was identified as a transcriptional activator of Hox genes required for the specification of body segment identities. To clarify the role of the BRM complex in the transcription of other genes, we exam...
Published in Cell
The brahma (brm) gene is required for the activation of multiple homeotic genes in Drosophila. Loss-of-function brm mutations suppress mutations in Polycomb, a repressor of homeotic genes, and cause developmental defects similar to those arising from insufficient expression of the homeotic genes of the Antennapedia and Bithorax complexes. The brm g...
Published in Molecular Cell
Drosophila ISWI, a highly conserved member of the SWI2/SNF2 family of ATPases, is the catalytic subunit of three chromatin-remodeling complexes: NURF, CHRAC, and ACF. To clarify the biological functions of ISWI, we generated and characterized null and dominant-negative ISWI mutations. We found that ISWI mutations affect both cell viability and gene...
Published in Development
The Drosophila trithorax group gene kismet (kis) was identified in a screen for extragenic suppressors of Polycomb (Pc) and subsequently shown to play important roles in both segmentation and the determination of body segment identities. One of the two major proteins encoded by kis (KIS-L) is related to members of the SWI2/SNF2 and CHD families of ...
Published in Development
The trithorax group gene brahma (brm) encodes an activator of Drosophila homeotic genes that functions as the ATPase subunit of a large protein complex. To determine if BRM physically interacts with other trithorax group proteins, we purified the BRM complex from Drosophila embryos and analyzed its subunit composition. The BRM complex contains at l...
Published in EMBO Reports
Mutations in Drosophila ISWI, a member of the SWI2/SNF2 family of chromatin remodeling ATPases, alter the global architecture of the male X chromosome. The transcription of genes on this chromosome is increased 2-fold relative to females due to dosage compensation, a process involving the acetylation of histone H4 at lysine 16 (H4K16). Here we show...
Published in Development
The Drosophila trithorax group gene kismet (kis) was identified in a screen for extragenic suppressors of Polycomb (Pc) and subsequently shown to play important roles in both segmentation and the determination of body segment identities. One of the two major proteins encoded by kis (KIS-L) is related to members of the SWI2/SNF2 and CHD families of ...
Published in Proceedings of the National Academy of Sciences
We have identified a Drosophila gene (arflike, arl) encoding a protein that is structurally related (approximately 55% identity) to the ADP-ribosylation factors (ARFs) of yeast and mammals. Biochemical analyses of purified recombinant arl-encoded protein revealed properties similar to the ARF proteins, including the ability to bind and hydrolyze GT...
