Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analysis of central Hox protein types across bilaterian clades: On the
  origin of central Hox proteins from an Antennapedia/Hox7-like ancestor   Hox proteins are one of the best studied sets of transcription factors in
developmental biology. They are major determinants for establishing
morphological differences along the anterior-posterior axis of animals and are
generally regarded as highly conserved in function. This view is based on
experiments comparing a few (anterior) Hox proteins, however, the extent to
which central or abdominal Hox proteins share sequence features or functions
remains largely unexplored. To shed light on the origin and functional
divergence of the central Hox proteins, we combine a powerful bioinformatics
tool (CLANS) with a large-scale phylogeny of species. CLANS is used to
differentiate between the various types of central Hox protein sequences, while
the phylogeny provides an evolutionary context to the analysis. The combination
of both enables us to infer the relative timepoint at which a given central Hox
protein type arose. We identify seven distinct central Hox protein sequence
types, only one of which is common to all protostome and deuterostome clades
(Antp/Hox7). Together, these results lead us to suggest reevaluating the
usefulness of the increasingly depicted synteny-based classification scheme
that assumes a one-to-one orthology between protostome and deuterostome central
Hox proteins. Instead, we propose that the use of sequence-based classification
schemes able to resolve the central and posterior Hox proteins provides a more
promising and biologically meaningful alternative to resolving these groups.
This analysis, which provides a unique overview of the Hox protein sequence
types present across protostomes and deuterostomes as well as a relative dating
for the emergence of the central Hox protein types, provides a crucial clue to
illuminate how and when the distinct developmental blueprints for organisms
evolved within the evolutionarily immensely successful bilaterian lineage.

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The categories of this paper are: cmp-lg
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The categories of this paper are: ao-sci
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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-th
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The categories of this paper are: chem-ph
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The categories of this paper are: eess
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The categories of this paper are: adap-org
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The categories of this paper are: astro-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-alg
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The categories of this paper are: hep-lat
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: funct-an
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The categories of this paper are: econ