Clusters of homeotic genes sculpt the morphology of animal body plans and body parts. Different body patterns may evolve through changes in homeotic gene number, regulation or function. Recent evidence suggests that homeotic gene clusters were duplicated early in vertebrate evolution, but the generation of arthropod and tetrapod diversity has largely involved regulatory changes in the expression of conserved arrays of homeotic genes and the evolution of interactions between homeotic proteins and the genes they regulate.

Homeotic genes and the evolution of arthropods and chordates

Variation in Homeodomain DNA Binding Revealed by High-Resolution Analysis of Sequence Preferences

Analysis of homeodomain specificities allows the family-wide prediction of preferred recognition sites

Extra specificity from extradenticle: the partnership between HOX and PBX/EXD homeodomain proteins.

Hox proteins are well known for executing highly specific functions in vivo , but our understanding of the molecular mechanisms underlying gene regulation by these fascinating proteins has lagged behind. The premise of this review is that an understanding of gene regulation—by any transcription factor—requires the dissection of the cis ‐regulatory elements that they act upon. With this goal in mind, we review the concepts and ideas regarding gene regulation by Hox proteins and apply them to a curated list of directly regulated Hox cis ‐regulatory elements that have been validated in the literature. Our analysis of the Hox‐binding sites within these elements suggests several emerging generalizations. We distinguish between Hox cofactors, proteins that bind DNA cooperatively with Hox proteins and thereby help with DNA‐binding site selection, and Hox collaborators, proteins that bind in parallel to Hox‐targeted cis ‐regulatory elements and dictate the sign and strength of gene regulation. Finally, we summarize insights that come from examining five X‐ray crystal structures of Hox‐cofactor‐DNA complexes. Together, these analyses reveal an enormous amount of flexibility into how Hox proteins function to regulate gene expression, perhaps providing an explanation for why these factors have been central players in the evolution of morphological diversity in the animal kingdom.

/pdf/hox-specificity-unique-roles-for-cofactors-and-collaborators-2u9a52s2d4.pdf

Hox specificity unique roles for cofactors and collaborators.

The homeodomain has been implicated as a major determinant of biological specificity for the homeotic selector (HOM) genes. We compare here the DNA sequence preferences of homeodomains encoded by four of the eight Drosophila HOM proteins. One of the four, Abdominal-B, binds preferentially to a sequence with an unusual 5'-T-T-A-T-3' core, whereas the other three prefer 5'-T-A-A-T-3'. Of these latter three, the Ultrabithorax and Antennapedia homeodomains display indistinguishable preferences outside the core while Deformed differs. Thus, with three distinct binding classes defined by four HOM proteins, differences in individual site recognition may account for some but not all of HOM protein functional specificity. We further show that amino acid residues within the N-terminal arm are responsible for the sequence specificity differences between the Ultrabithorax and Abdominal-B homeodomains. Similarities and differences at the corresponding positions within the N-terminal arms are conserved in the vertebrate Abdominal-B-like HOM proteins, which play critical roles in limb specifications as well as in regional specification along the anterior-posterior axis. This and other patterns of residue conservation suggest that differential DNA sequence recognition may play a role in HOM protein function in a wide range of organisms.

https://www.embopress.org/doi/pdf/10.1002/j.1460-2075.1994.tb06662.x

The degree of variation in DNA sequence recognition among four Drosophila homeotic proteins

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

D.G. Jackson

Author Tools

Chat about Author

Papers

The degree of variation in DNA sequence recognition among four Drosophila homeotic proteins