23Proc. Arthropod. Embryol. Soc. Jpn. 52, 23–24 (2019)Ⓒ 2019 Arthropodan Embryological Society of Japan
ISSN 1341–1527

Body Axis Segmentation in the Common House Spider Parasteatoda
tepidariorum: Identification of Gene Expression Waves That Pattern
Conserved Stripes in a Cell-based Field*Hiroki ODA1, 2)
JT Biohistory Research Hall, Laboratory of Evolutionary Cell and Developmental Biology, 1–1 Murasaki-cho, Takatsuki, Osaka 569–1125, Japan2)
Department of Biological Sciences, Graduate School of Science, Osaka University
E-mail: hoda@brh.co.jp
1)

The common house spider Parasteatoda tepidariorum(Chelicerata) has emerged as a non-insect arthropod model
for studying developmental and evolutionary mechanisms(Oda and Akiyama-Oda, 2008; Hilbrant et al., 2012). Its
genome has been sequenced by the Baylor College of Medicine
Human Genome Sequencing Center and the international P.
tepidariorum genome consortium (Schwager et al., 2017).
Our group also accumulated genomic and transcriptomic
sequences from our laboratory stocks of the spider isolatedin Japan (Oda et al., 2007; Sasaki et al., 2017), which areavailable at our data resource site (http://www.brh2.jp) aswell as at the DDBJ/EMBL/GenBank Nucleotide Sequences
Databases. Besides these sequence resources, there are anumber of benefits associated with the use of P. tepidariorum.
Its phylogenetic position, distant from insects within theArthropoda phylum, may help conduct comparative studies oflooking deep into the evolutionary root of arthropod animals.
In contrast to most insect embryos, which are syncytia at
early stages, spider embryos undergo patterning in a cellularenvironment from the early stages (Kanayama et al., 2010),
which could enhance the significance of the comparativestudies. Experimental techniques available in this spider, suchas parental and embryonic RNA interference (RNAi), facilitate
in-depth analyses of developmental mechanisms at the celland molecular levels. Parental RNAi can silence target geneactivity in early whole embryos (Akiyama-Oda and Oda, 2006),and embryonic RNAi enables one to analyze gene function incell clones in the normal background (Kanayama et al., 2011), asin mosaic analysis in Drosophila larvae. More importantly, theRNAi techniques can be effectively combined with genomewide, non-biased gene discovery analysis based on nextgeneration sequencing techniques (Yasuko Akiyama-Oda andH. Oda, in prep.). Therefore, we believe that the P. tepidariorum
embryo provides an ideal cell-based platform with which to
study mechanisms of pattern formation and their evolution inarthropods.
One of the major patterning events observed among all

arthropod embryos is body axis segmentation, in which stripesof gene expression develop dynamically in the embryonic field
through processes varied among regions of the field, although
the output stripe patterns of gene expression (e.g., stripesof segment polarity gene expression) are highly conserved
irrespective of insect or non-insect arthropods. However,
little is understood about the basis of molecular and genetic
mechanisms that generate a diversity of stripe-forming
processes in a cell-based field of an arthropod embryo. Thisissue may be associated with one of the biggest questions in
the EVO-DEVO field, what ancestral state of development
enabled the evolution of a diversity of patterning processes ina phylum.
To pursue our research in this direction using the P.
tepidariorum model, we conducted a quantitative study ofstripe-forming processes as well as genome-wide identificationof genes whose expression levels are regulated by Hedgehog
signaling pathway components, which were previously shown
to be involved in axis formation in the spider embryo (AkiyamaOda and Oda, 2010). In this talk, based on data we obtained inprevious and present studies (Akiyama-Oda and Oda, 2010;
Kanayama et al., 2011), we suggest that mechanisms that
operate waves of gene expression are fundamental to spider
body axis segmentation in all regions of the embryonic field.
References
Akiyama-Oda, Y. and H. Oda (2006) Axis specification in thespider embryo: dpp is required for radial-to-axial symmetrytransformation and sog for ventral patterning. Development, 133,2347–2357.
Akiyama-Oda, Y. and H. Oda (2010) Cell migration that orients thedorsoventral axis is coordinated with anteroposterior patterning
mediated by Hedgehog signaling in the early spider embryo.
Development, 137, 1263–1273.
Hilbrant, M., W.G. Damen and A.P. McGregor (2012) Evolutionary
crossroads in developmental biology: the spider Parasteatoda
tepidariorum. Development, 139, 2655–2662.

* Abstract of paper read at the 53rd Annual Meeting of the Arthropodan Embryological Society of Japan, May 26–27, 2017 (Gamagori, Aichi).

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Kanayama, M., Y. Akiyama-Oda, O. Nishimura, H. Tarui, K. Agataand H. Oda (2011) Travelling and splitting of a wave of hedgehog

differentiation, 50, 203–214.
Sasaki, M., Y. Akiyama-Oda and H. Oda (2017) Evolutionary origin

expression involved in spider-head segmentation. Natureof type IV classical cadherins in arthropods. BMC evolutionarycommunications, 2, 500.

biology, 17, 142.

Kanayama, M., Y. Akiyama-Oda and H. Oda (2010) Early embryonicdevelopment

inthespider

Achaearanea

tepidariorum:

Schwager, E.E., P.P. Sharma, T. Clarke, D.J. Leite, T. Wierschin, M.
Pechmann, Y. Akiyama-Oda, L. Esposito, J. Bechsgaard, T. Bilde,

microinjection verifies that cellularization is complete before theA.D. Buffry, H. Chao, H. Dinh, H. Doddapaneni, S. Dugan, C.

blastoderm stage. Arthropod structure & development, 39, 436–

Eibner, C.G. Extavour, P. Funch, J. Garb, L.B. Gonzalez, V.L.

445.

Gonzalez, S. Griffiths-Jones, Y. Han, C. Hayashi, M. Hilbrant,Oda, H., O. Nishimura, Y. Hirao, H. Tarui, K. Agata and Y. Akiyama-

D.S.T. Hughes, R. Janssen, S.L. Lee, I. Maeso, S.C. Murali, D.M.

Oda (2007) Progressive activation of Delta-Notch signaling fromMuzny, R. Nunes da Fonseca, C.L.B. Paese, J. Qu, M. Ronshaugen,around the blastopore is required to set up a functional caudal lobe

C. Schomburg, A. Schönauer, A. Stollewerk, M. Torres-Oliva, N.

in the spider Achaearanea tepidariorum. Development, 134, 2195–

Turetzek, B. Vanthournout, J.H. Werren, C. Wolff, K.C. Worley, G.

2205.

Bucher, R.A. Gibbs, J. Coddington, H. Oda, M. Stanke, N.A. Ayoub,Oda, H. and Y. Akiyama-Oda (2008) Differing strategies for forming

N.M. Prpic, J.F. Flot, N. Posnien, S. Richards and A.P. McGregor

the arthropod body plan: lessons from Dpp, Sog and Delta in the(2017) The house spider genome reveals an ancient whole-genome

fly Drosophila and spider Achaearanea. Development, growth &duplication during arachnid evolution. BMC biology, 15, 62.