@article{Jackson_Wörheide_Degnan_2007,
title = {{Dynamic expression of ancient and novel molluscan shell genes during ecological transitions.}},
volume = {7},
issn = {1471-2148},
url = {http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2034539&tool=pmcentrez&rendertype=abstract},
doi = {10.1186/1471-2148-7-160},
abstractnote = {BACKGROUND: The Mollusca constitute one of the most morphologically and ecologically diverse metazoan phyla, occupying a wide range of marine, terrestrial and freshwater habitats. The evolutionary success of the molluscs can in part be attributed to the evolvability of the external shell. Typically, the shell first forms during embryonic and larval development, changing dramatically in shape, colour and mineralogical composition as development and maturation proceeds. Major developmental transitions in shell morphology often correlate with ecological transitions (e.g. from a planktonic to benthic existence at metamorphosis). While the genes involved in molluscan biomineralisation are beginning to be identified, there is little understanding of how these are developmentally regulated, or if the same genes are operational at different stages of the mollusc’s life. RESULTS: Here we relate the developmental expression of nine genes in the tissue responsible for shell production - the mantle - to ecological transitions that occur during the lifetime of the tropical abalone Haliotis asinina (Vetigastropoda). Four of these genes encode evolutionarily ancient proteins, while four others encode secreted proteins with little or no identity to known proteins. Another gene has been previously described from the mantle of another haliotid vetigastropod. All nine genes display dynamic spatial and temporal expression profiles within the larval shell field and juvenile mantle. CONCLUSION: These expression data reflect the regulatory complexity that underlies molluscan shell construction from larval stages to adulthood, and serves to highlight the different ecological demands placed on each stage. The use of both ancient and novel genes in all stages of shell construction also suggest that a core set of shell-making genes was provided by a shared metazoan ancestor, which has been elaborated upon to produce the range of molluscan shell types we see today.},
journal = {BMC evolutionary biology},
author = {Jackson, Daniel J and Wörheide, Gert and Degnan, Bernard M},
year = {2007},
month = {Jan},
pages = {160},
}
@article{Jackson_McDougall_Green_Simpson_Wörheide_Degnan_2006,
title = {{A rapidly evolving secretome builds and patterns a sea shell.}},
volume = {4},
issn = {1741-7007},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17121673},
doi = {10.1186/1741-7007-4-40},
abstractnote = {BACKGROUND: Instructions to fabricate mineralized structures with distinct nanoscale architectures, such as seashells and coral and vertebrate skeletons, are encoded in the genomes of a wide variety of animals. In mollusks, the mantle is responsible for the extracellular production of the shell, directing the ordered biomineralization of CaCO3 and the deposition of architectural and color patterns. The evolutionary origins of the ability to synthesize calcified structures across various metazoan taxa remain obscure, with only a small number of protein families identified from molluskan shells. The recent sequencing of a wide range of metazoan genomes coupled with the analysis of gene expression in non-model animals has allowed us to investigate the evolution and process of biomineralization in gastropod mollusks. RESULTS: Here we show that over 25% of the genes expressed in the mantle of the vetigastropod Haliotis asinina encode secreted proteins, indicating that hundreds of proteins are likely to be contributing to shell fabrication and patterning. Almost 85% of the secretome encodes novel proteins; remarkably, only 19% of these have identifiable homologues in the full genome of the patellogastropod Lottia scutum. The spatial expression profiles of mantle genes that belong to the secretome is restricted to discrete mantle zones, with each zone responsible for the fabrication of one of the structural layers of the shell. Patterned expression of a subset of genes along the length of the mantle is indicative of roles in shell ornamentation. For example, Has-sometsuke maps precisely to pigmentation patterns in the shell, providing the first case of a gene product to be involved in molluskan shell pigmentation. We also describe the expression of two novel genes involved in nacre (mother of pearl) deposition. CONCLUSION: The unexpected complexity and evolvability of this secretome and the modular design of the molluskan mantle enables diversification of shell strength and design, and as such must contribute to the variety of adaptive architectures and colors found in mollusk shells. The composition of this novel mantle-specific secretome suggests that there are significant molecular differences in the ways in which gastropods synthesize their shells.},
journal = {BMC biology},
author = {Jackson, Daniel J and McDougall, Carmel and Green, Kathryn and Simpson, Fiona and Wörheide, Gert and Degnan, Bernard M},
year = {2006},
month = {Jan},
pages = {40},
}
@article{25912046,
title = {{The Magellania venosa biomineralizing proteome: a window into brachiopod shell evolution.}},
date = {2015 Apr 24},
source = {Genome Biol Evol},
authors = {Jackson, DJ and Mann, K and Häussermann, V and Schilhabel, M and Lüter, C and Griesshaber, E and Schmahl, W and Wörheide, G},
author = {Jackson, DJ and Mann, K and Häussermann, V and Schilhabel, M and Lüter, C and Griesshaber, E and Schmahl, W and Wörheide, G},
year = {2015},
month = {Apr},
journal = {Genome Biol Evol},
volume = {},
number = {},
pages = {},
pubmed_id = {25912046},
}
@article{24343243,
title = {{Symbiophagy and biomineralization in the living fossil Astrosclera willeyana.}},
date = {2014 Mar},
source = {Autophagy},
authors = {Jackson, DJ and Wörheide, G},
author = {Jackson, DJ and Wörheide, G},
year = {2014},
month = {},
journal = {Autophagy},
volume = {10},
number = {},
pages = {408-15},
pubmed_id = {24343243},
}
@article{Feuda:2015ew,
author = {Feuda, Roberto and Smith, Andrew B},
title = {{Phylogenetic Signal Dissection Identifies the Root of Starfishes}},
journal = {PLoS ONE},
year = {2015},
volume = {10},
number = {5},
pages = {e0123331},
month = {may},
doi = {10.1371/journal.pone.0123331},
issn = {1932-6203},
language = {English},
read = {Yes},
rating = {0},
date-added = {2015-05-16T09:31:57GMT},
date-modified = {2015-05-17T11:32:45GMT},
abstract = {Relationships within the class Asteroidea have remained controversial for almost 100 years and, despite many attempts to resolve this problem using molecular data, no consensus has yet emerged. Using two nuclear genes and a taxon sampling covering the major asteroid clades we show that non-phylogenetic signal created by three factors - Long Branch Attraction, compositional heterogeneity and the use of poorly fitting models of evolution {\textendash} have confounded accurate estimation of phylogenetic relationships. To overcome the effect of this non-phylogenetic signal we analyse the data using non-homogeneous models, site stripping and the creation of subpartitions aimed to reduce or amplify the systematic error, and calculate Bayes Factor support for a selection of previously suggested topological arrangements of asteroid orders. We show that most of the previous alternative hypotheses are not supported in the most reliable data partitions, including the previously suggested placement of either Forcipulatida or Paxillosida as sister group to the other major branches. The best-supported solution places Velatida as the sister group to other asteroids, and the implications of this finding for the morphological evolution of asteroids are presented.},
url = {http://dx.plos.org/10.1371/journal.pone.0123331},
}
