Plasticity in patterns of histone modifications and chromosomal proteins in Drosophila heterochromatin

In Drosophila melanogaster, the borders between pericentric heterochromatin and euchromatin on the major chromosome arms have been defined in various ways, including chromatin-specific histone modifications, the binding patterns of heterochromatin-enriched chromosomal proteins, and various cytogenetic techniques. Elucidation of the genetic properties that independently define the different chromatin states associated with heterochromatin and euchromatin should help refine the boundary. Since meiotic recombination is present in euchromatin, but absent in heterochromatin, it constitutes a key genetic property that can be observed transitioning between chromatin states. Using P element insertion lines marked with a su(Hw) insulated mini-white gene, meiotic recombination was found to transition in a region consistent with the H3K9me2 transition observed in ovaries.

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Molecular cloning of a human homologue of Drosophila heterochromatin protein HP1 using anti-centromere autoantibodies with anti-chromo specificity

Journal of Cell Science ◽

10.1242/jcs.104.2.573 ◽

1993 ◽

Vol 104 (2) ◽

pp. 573-582 ◽

Cited By ~ 8

Author(s):

W.S. Saunders ◽

C. Chue ◽

M. Goebl ◽

C. Craig ◽

R.F. Clark ◽

...

Keyword(s):

Epitope Mapping ◽

Structural Motif ◽

Amino Terminus ◽

Cdna Clones ◽

Human Homologue ◽

Expression Library ◽

Heterochromatin Protein ◽

Chromosomal Proteins ◽

Drosophila Heterochromatin ◽

Drosophila Heterochromatin Protein

We have identified a novel autoantibody specificity in scleroderma that we term anti-chromo. These antibodies recognize several chromosomal antigens with apparent molecular mass of between 23 and 25 kDa, as determined by immunoblots. Anti-chromo autoantibodies occur in 10–15% of sera from patients with anti-centromere antibodies (ACA). We used anti-chromo antibodies to screen a human expression library and obtained cDNA clones encoding a 25 kDa chromosomal autoantigen. DNA sequence analysis reveals this protein to be a human homologue of HP1, a heterochromatin protein of Drosophila melanogaster. We designate our cloned protein HP1Hs alpha. Epitope mapping experiments using both human and Drosophila HP1 reveal that anti-chromo antibodies target a region at the amino terminus of the protein. This region contains a conserved motif, the chromo domain (or HP1/Pc box), first recognized by comparison of Drosophila HP1 with the Polycomb gene product. Both proteins are thought to play a role in creating chromatin structures in which gene expression is suppressed. Anti-chromo thus defines a novel type of autoantibody that recognizes a conserved structural motif found on a number of chromosomal proteins.

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How do histone modifications contribute to transgenerational epigenetic inheritance in C. elegans?

Biochemical Society Transactions ◽

10.1042/bst20190944 ◽

2020 ◽

Vol 48 (3) ◽

pp. 1019-1034 ◽

Cited By ~ 1

Author(s):

Rachel M. Woodhouse ◽

Alyson Ashe

Keyword(s):

Histone Modifications ◽

Molecular Mechanisms ◽

Epigenetic Inheritance ◽

Nematode Caenorhabditis Elegans ◽

Histone Methyltransferases ◽

Transgenerational Epigenetic Inheritance ◽

C Elegans ◽

Recent Developments ◽

Gene Regulatory

Gene regulatory information can be inherited between generations in a phenomenon termed transgenerational epigenetic inheritance (TEI). While examples of TEI in many animals accumulate, the nematode Caenorhabditis elegans has proven particularly useful in investigating the underlying molecular mechanisms of this phenomenon. In C. elegans and other animals, the modification of histone proteins has emerged as a potential carrier and effector of transgenerational epigenetic information. In this review, we explore the contribution of histone modifications to TEI in C. elegans. We describe the role of repressive histone marks, histone methyltransferases, and associated chromatin factors in heritable gene silencing, and discuss recent developments and unanswered questions in how these factors integrate with other known TEI mechanisms. We also review the transgenerational effects of the manipulation of histone modifications on germline health and longevity.

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