CENTER FOR THE DEVELOPMENT OF NEW MODEL ORGANISMSSUZUKI GroupSpecially Appointed Associate Professor(Cross-appointment with Hiroshima University)
HeadUENO, NaotoProfessor

SHIGENOBU, Shuji

Specially Appointed Associate Professor

SUZUKI, Ken-ichi

Postdoctoral Fellow:
Technical Assistant:

KISHIMOTO, Mariko
SHIBATA, Yuki
TAKAYAMA, Ayuko
SANBO, Chiaki

Since the beginning of life on Earth, living organisms have
evolved to adapt to various environments, and have spawned
a wide variety of species. Modern biological research hasput an emphasis on elucidating the basic principles commonto many species, and has progressed thanks to the intensive
analysis of a limited number of species known as modelorganisms, which are easy to handle in a laboratory environment. However, this development has most likely leftmany interesting biological phenomena unexamined as their
distinctive characteristics are observed only in a particulargroup of species. How we overcome this is an important
challenge for biology hereafter.
To solve these problems, we must choose a species mostsuitable to analyze the phenomenon to be researched, andthen establish it as a new model organism by developing
methods using procedures that are necessary for modern
biological analyses. These include stable raising, breedingand experimental manipulation techniques, analyses of thegenome information and gene expression, and gene manipulation techniques using gene insertion and genome editing
techniques.
To this end, The Center for the Development of New Model
Organisms was established in 2013. Through its activities,
organisms that have been out of reach of scientific researchwere designated as new model organisms. For example,
we study aphids and sea anemones to understand the symbioses, and rhinoceros beetles to get insights into the sexualdimorphism. We are refining various techniques for studying
targeted new model organisms ranging from genome analysis
to genetic engineering to build seamless workflows that will
be shared among the research community.

SUZUKI, Ken-ichi

Postdoctoral Fellow:
Technical Assistant:

SHIBATA, Yuki
TAKAYAMA, Ayuko
SANBO, Chiaki

Two technical innovations have recently changed biology:
Next generation sequencing (NGS) and Genome editing.
NGS reveals whole genome sequences and gene expression
profiles from various organisms. Genome editing accelerates
the functional characterization of numerous genes involvedin the phenomenon of life. Accordingly, we are now basicallyable to choose any organism which we are interested in, andcarry out functional analyses by using these tools.

1-1 D evelopment of genome editing techniques forvarious organisms.
Recent advances in the CRISPR-Cas system now allow
for reverse genetics in various organisms. However, it has
been hampered by the lack of a simple and efficient method
for gene modification in most of the non-model organisms. To overcome this issue, we developed a highly-efficient workflow for gene knockout in the founder using thisCIRSPR-Cas. We call the virtually knockout founders “crispants”. Crispant assay provides us with a practical and rapid
tool for functional screening of numerous genes of interest
beyond the post-genome era (Figure 1).
Despite the practical utility of the knockout technique, there
is still room for improvement in the integration of exogenous
DNA into a target chromosomal site (i.e. knock-in), whichis still somewhat limited in various organisms. Therefore,
we are currently developing more efficient and practicalknock-in techniques than conventional ones.

Research activity by S. Shigenobu

Professor Shuji Shigenobu is the principal investigator of
the Laboratory of Evolutionary Genomics. Refer to the laboratory page for details.

Figure 1. tyrosinase crispant in P. waltl. A knock-out founder of tyrosinase, a melanin synthesis enzyme, and wild newt (left and right, respectively). tyr crispant shows full albinism.

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National Institute for Basic Biology

Research Support

1-2 Finding new model organisms and decipheringorgan regeneration

One of our missions is to discover unique organisms anddevelop them as new model organisms for basic biology.
A recent example of this is our recent establishment of thenewt Pleurodeles waltl as an experimental model animal forregenerative biology using NGS and genome editing techniques. P. waltl possesses several excellent characteristics
as a model animal: easy breeding, short sexual maturation
period, remarkable regenerative capacity and comparatively
high efficiency of genome editing (Figure 2). We are currently researching the molecular basis of organ regeneration
using this newt. In addition, we widely support researchers
who attempt to develop new model organisms contributing tothe up-coming biology.

Figure 2. A limb-specific enhancer (ZRS/MFCS1) of sonic hedgehog
crispant in P. waltl. Phenotypes of limb regeneration in wild and ZRS/MFCS1 crispant (left and right, respectively). Unlike in normal limb
regeneration in the wild type, severe reduction of digit formation wasseen in ZRS/MFCS1 crispant.

Publication List:〔Original papers〕

T., Matsubara, H., Minamitani, F., Satoh, Y., Tozawa, S.,• Takeuchi,Moriyama, T., Maruyama, K., Suzuki, K.T., Shigenobu, S., Inoue, T.,

Tamura, K., Agata, K., and Hayashi, T. (2022). Newt Hoxa13 has an
essential and predominant role in digit formation during development
and regeneration. Development 149, dev200282. DOI: 10.1242/
dev.200282

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