Current Biology

Magazinetailings in the deep ocean and their
biological impacts is a significant cause
for concern.” The material can smotherecosystems at the disposal site, andif toxic metal ions are released into
the water they may end up in the foodweb. The EU is currently producing
new guidelines for best practice in themarine disposal of mining waste.
On top of these legally permitted
assaults on the oceans, there are theirregular and illegal waste disposals
which are very difficult to police on
the oceans, along with the accidental
pollution from shipwrecks andaccidents on drilling platforms. Large
numbers of ships rest on the sea floor,
where the more modern ones may
be slowly leaking their fuel and toxic
materials. Until the case of the Shell
platform Brent Spar made headlines
around the world in 1995, it was also
deemed acceptable to dump suchvast structures instead of towing themback for recycling on land.
Finally, the swelling tide of plastic
waste washed out to sea and broken
down to microscopic particles that
may enter the food web has become
a considerable concern over recentyears (Curr. Biol. (2015) 25, R93–R96).
Overall, the oceans, including thedeeper waters, are already exposedto large amounts of anthropogenic
pollution, and much more research
will be needed to establish how thiswill affect the ecology of the oceans.
Conflicts of conscience
While the problems outlined above
can mostly be described as conflicts
between economic interests and theconservation of a natural environment,
there is also the growing prospect ofenvironmentally motivated actions
that will in turn impact the marine
environment, requiring carefullybalanced decisions based on soundscientific knowledge.
Even the greenest technologies
can have side effects. Off-shore
wind turbines, for instance, require
sacrificial anodes, which releaselarge amounts of zinc into the water.
Tidal energy installations may disrupt
the local ecosystems, as largehydroelectric dams do on land.
The EMB report discusses in detailthe prospect of producing ‘blueenergy’ from the temperature gradient
between the cold deep waters(2°C) and warm surface waters.
As a temperature difference of atleast 20°C is required for economic
efficiency, this would only be an
option in tropical waters. Comparedwith solar and wind power, the Ocean
Thermal Energy Conversion (OTEC)
technology has the advantage thatit can supply a constant baseload
at all times. It is particularlycompetitive when supplying islandand coastal locations that are far fromconventional power sources.
An open system allowing seawater
itself to circulate between the layers
would produce an unnatural mixing
process that could have side effects,
the report notes. By contrast, aclosed system with a sealed-in liquid
circulating could avoid this and achieve
higher efficiency using other fluids
such as ammonia. In any case, theindustrial scale required to make such
installations economically viable, alongwith the surrounding infrastructure, arelikely to have an environmental impact.
The company Lockheed Martin iscurrently developing a 10MW OTEC
plant for a zero-carbon resort to bebuilt in southern China, which is due tobecome operational in 2017.
While OTEC plants may stir up theoceans locally and to a modest extent,
more dramatic effects are expectedfrom plans to avert catastrophic
climate change by fiddling with theEarth system, also known as geoengineering. Some of the interventions
considered, like iron fertilisation with aview to increase carbon sequestration(Curr. Biol. (2009) 19, R143–R144), arealso bound to affect the deep waters.
In all of these issues likely to impact
upon the ecology of the deep sea, it isobvious that our scientific knowledge
base is not nearly sufficient to warrant
that we can find ways of developing
the blue economy in a sustainable
way. If the industrialisation of thedeep sea rushes ahead and thescience comes trundling after toassess the collateral damage,humanity is bound to repeat on thesea floor the same mistakes it has
made on land. For the sake of the life
blood of our blue planet, we should
put scientific understanding first.
Michael Gross is a science writer based at
Oxford. He can be contacted via his web pageat www.michaelgross.co.uk

Q&A

Tatsuo Fukagawa
Tatsuo Fukagawa was born and brought
up in Tokyo, Japan. He graduated from
Hokkaido University in 1991 and earned
his PhD in Genetics from the National
Institute of Genetics (Department ofGenetics, Graduate University for
Advanced Studies) in 1995. As apostdoc, Tatsuo (“Tats”) worked with
William Brown in Ed Southern’s lab
in the Department of Biochemistryat the University of Oxford, where heestablished a technique to efficiently
engineer genomes and chromosomes
using chicken DT40 cells. In 1999, hejoined the National Institute of Genetics
as an Assistant Professor, where hebegan investigating the moleculararchitecture of centromeres/kinetochores
using a combination of disciplines suchas genetics, biochemistry, cell biology,
genome sciences, and structuralbiology. He has been promoted throughthe ranks to the current position ofProfessor, as of 2008, in the National
Institute of Genetics. In 2015, Tats
moved to the Graduate School ofFrontier Bioscience at Osaka University.
What turned you on to biology inthe first place? When I was a student
in junior high school, I was interested
in humanities rather than naturalsciences. I loved to study the historyof Japan and imagined how leaders
made their decisions in each period. I
especially liked leaders in the transition
from the Edo Era to the Meiji Era,
which is called ‘The Meiji Restoration’(Meiji Ishin). In that period, there weremany changes in Japan. Because Iwas also interested in studying politicalscience, I planned to take a course in
the department of political science ina university, when I was a high school
student. However, I found that it washard to visualize achievements that
could be made in the field of politicalscience. I completely changed mymind at that point, and wanted to workwith visual products. Since Japan isa small country, there are few foodresources. However, the developmentof science technologies is active inJapan. Therefore, I decided to tackle
the challenge of generating usefulfood resources using biotechnologicalapproaches.

Current Biology 25, R1019–R1031, November 2, 2015 ©2015 Elsevier Ltd All rights reserved

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Current Biology

MagazineFirst, I took a course on ‘Food
Science and Technology’ at Hokkaido
University. Although I tried to workon genetic engineering of marine
bacteria in an undergraduate course,
I became acutely aware that I had togain additional knowledge in molecularbiology to successfully work in thefield of genetic engineering. At thattime, I realized that without a deep
understanding of basic science, we
can never carry out research in the fieldof applied science. I decided to enroll
in a graduate course at the National
Institute of Genetics (NIG) to study basic
molecular biology and genetics.
What did you learn at NIG? I reallyenjoyed my graduate course at NIG. I
learned a lot of basic molecular biology
and genetics, as well as experimental
skills in related areas at NIG. I was soeager to conduct experiments thatsometimes I would even forget to eat
my meals. I really concentrated on
performing these experiments. Although
I enrolled in the graduate course todevote my work to applied science, I
found I liked molecular biology muchmore. Later in my graduate course,
I started to think about postdoctoral
study abroad in the field of molecularbiology.
Why did you choose Oxford for yourpostdoctoral training? I studied
human genome organization as a main
project in my graduate course at NIG.
We focused on chromosome banding
patterns in humans and tried to identify
band boundaries at the molecular levelto understand the biological significanceR1022of chromosome banding. Because acomplete genome was not available atthat time, I did chromosome walking
from a high-GC rich region to a low-GC
rich region and finally cloned the sharpboundaries of chromosome bands.
These corresponded to the boundaries
in timing of DNA replication. Although it
was a rather fun project, the biologicalsignificance of chromosome banding
was not so clear. I decided I would liketo study more on defined functional
chromosomal domains, such as
centromeres and telomeres. One day, I
read a paper by William Brown and hiscolleagues, which described trials tocreate a human artificial chromosome(HAC) through a telomere-directed
breakage assay. I was very impressedby their unusual approach, and wasalso aware that William and some of
his colleagues worked in the lab of Ed
Southern, the famous inventor of the‘Southern blot’ technique. I expected
to gain new insights by working with
William and Ed and decided to join
Oxford as a postdoctoral fellow.
How was life in Oxford? Japan is amore isolated country than Europe,and it was the first time I was living in
a foreign country. At first, it was not soeasy for me and my family to adjust
to life in England. Language was adefinite problem, making it difficult tocommunicate with colleagues, and I
was mostly silent when I started goingto Oxford. However, I worked very
hard in the lab and, within a year, I had
established a conditional knockoutchicken DT40 cell line for CENP-C.
At that time, chicken DT40 was not amajor experimental system, and William
had just introduced these cells to his
team as a host to create HACs. Since
DT40 shows frequent homologous
recombination, he imagined thatDT40 cells would be a good system
for the telomere-directed breakage
assay. I myself tried to use this cellline to analyze gene function through agene-knockout approach. Since I wasinterested in centromeres, I tried toclone a chicken homologue of CENP-C,
which had just been identified as acentromere protein in humans, andto establish a conditional knockout
for CENP-C. Although this was nota super achievement, I devised amethod to make conditional knockout
cells by myself and then generated

the cell lines. At this point, colleagues
recognized me as a talented postdoc
and I gained the confidence to doresearch at Oxford. I made good friends
there, who were very kind and helpfulfor my studies. After this, I enjoyedlife for the next 3 years in Oxford. Ofcourse, I learned serious scientificattitudes from William and Ed.
Then, did you go back to Japan? Yes.
One night, I got a telephone call frommy Japanese mentor, Prof. Toshimichi
Ikemura, asking me whether I would
be interested in an Assistant Professor
position at NIG. As you may know, thesystem in Japanese universities andinstitutes is quite different from that inthe USA. There were no independent
positions for young scientists at thattime. Currently, the Japanese system
is changing. Now, young scientists canlook for independent positions in eachuniversity, even though there still are notmany positions. Even if this offer was anAssistant Professor position, I would beworking in a team under Prof. Ikemura.
If I wanted an independent position, Iwould have to apply for such positionsin the USA or Europe. I thought deeply
about my future, and I decided to go
back to Japan. I was sure that I wouldfind merits in Japanese research andcould conduct proper good sciencein this country. Fortunately, Prof.
Ikemura allowed me to take up my own
project. In this project, I tried to identify
new kinetochore components fromchicken DT40 cells under the guidanceof his team. I greatly appreciate hisgenerous attitude. After three years, I
was provided with my own lab in NIG
and continued to study centromeres/
kinetochores independently. I consider
myself very lucky.
What is the most exciting result inyour scientific experience? I love lab
work, and so I am always excited to see
new results. The most exciting result
may have been my first look at a new
kinetochore protein. When we tried toidentify new kinetochore components
using a proteomics approach in early
2000, we found sequences of new
candidates for kinetochore components.
We cloned full-length cDNA of eachcandidate based on these sequences
and made GFP-fused cDNAs. We
checked the expression and localizationof each GFP-fused clone under theCurrent Biology 25, R1019–R1031, November 2, 2015 ©2015 Elsevier Ltd All rights reservedCurrent Biology

Magazinemicroscope. After looking at many
images of negative clones, I was very
excited to observe nice punctate signals
in the nucleus, suggesting a positiveclone. I remember that I cried in the darkroom. By continuing this experiment,
we found many constitutive centromere
proteins, which are now called ‘CCAN’proteins. This series of experiments
determined the direction of my research
career.
Do you continue to study
centromeres/kinetochores? Yes. In thetwo decades since this experiment, wehave continued to look for componentsof kinetochores, and I believe that mostcomponents have been identified. Thenext question is how these proteinsare organized to generate functional
kinetochores. Since there are over
100 different kinetochore proteins, it
is not easy to address this question.
At the same time, several researchers,
including our lab, began to reconstitutea part of the kinetochore structure.
Although this is a very important
experiment, we had to first understandthe organization of the native
kinetochore structure. I believe that
understanding kinetochore structure andfunction is the best way to understandhow chromosomes segregate equallyinto daughter cells. There are many
important general questions that weshould address in biology. You mightfeel that studies on chromosome
segregation or kinetochore structure
are a bit restricted or limited, but thatis not true. If we continue our studies
in this field, we may find answers tounexpected new questions, because
chromosomes are the fundamental
structures in every cell. For this reason, I
would like to encourage young scientists
to join this field. I am sure that we will
still get to reveal several unexpectedphenomena in this area of science.
Is Japan a good place to conduct
research? This is a difficult question.
Of course, we have a strong traditionof chromosome research, and there
are many researchers in Japan working
on chromosomes. Needless to say,though, the centers of scientific researchare based in the USA and Europe. For
example, major journals are published in
the USA or Europe. Therefore, we must
communicate with scientists in the USA
or Europe. Today, as communication

tools are well developed, it is possible totalk easily with scientists abroad using
Skype or email. However, it is still muchbetter to talk with colleagues in person,
and these opportunities are limited. In
addition, many talented students andpostdocs want to join labs in the USA orEurope. Considering this, I cannot saythat Japan is the best country in whichto conduct science. However, there areclear merits in Japanese science. For
example, Japanese people are goodat teamwork, and individual abilities ofJapanese students are not less thanthose of students in the USA. Although
we are generally not very skilled atwriting manuscripts or responding
effectively to hard reviews, we canlearn many things from the scientificcommunities in the USA and Europe
through this process. I have actually
received many useful suggestions from
reviewers, and this process trained
me quite well, and could also be donein Japan. If I organize a good team inJapan, utilizing these merits in Japanesescience, I believe that we can produce
better scientific achievements fromJapan. I recently moved to a new place(Osaka University). Here, I will try toorganize the best team possible.
Since I have been supported by theJapanese scientific community, I feel
obligated to train young Japanesescientists to be active in scientificresearch as part of the world community.
In recent years, the Japanese
government has been promoting
globalization. True globalization ispossible if each scientist is active andrecognized in his or her research field.
Recently, the Japanese government
has also demonstrated a trend towards
supporting medical science rather thanbasic science in the field of biology.
However, as I learned early on, excellent
research in the field of applied science(including medical science) requires a
deep understanding of basic science.
Since Japan has a strong background inchromosome research, I hope that theJapanese government will continue tosupport our basic research, which willcontribute to the overall developmentof medical research and help to train
excellent ‘global’ young scientists.
Graduate School of Frontier Biosciences,
Osaka University, Suita, Osaka 565-0871,Japan.
E-mail: tfukagawa@fbs.osaka-u.ac.jp

Quick guide

Predatory
grasshopper mice
Ashlee H. Rowe* and Matthew P. Rowe
What are grasshopper mice?
Grasshopper mice are big-eared, bigeyed, nocturnal rodents closely related
to deer mice. They are relatively small(they are mice, after all!), only 120–190
mm long, about the length of a pencil,
including their stubby, fat tail; adults
typically weigh between 20 and 50grams, the weight of about eight pennies
for a small individual, 20 pennies for abruiser. There are just three species, allin the genus Onychomys, the southern,
northern, and Mearns’ (or Chihuahuan)grasshopper mouse, respectively. Theirgeographical distribution is restricted tothe short-grass prairies, shrub deserts,
and desert grasslands of the western
United States and northern Mexico, withthe range of one species, the northerngrasshopper mouse, extending into thenorthern Great Plains of south-central
Canada.
Why are they called ‘grasshopper
mice’? The mice earned this epithet
because they aren’t the timid, hidein-the-corners, seed-eating, cheesestealing pantry pests many people thinkof when they hear the label ‘mouse’.
They are top-level carnivores, ferocious
killers little different, besides theirdiminutive size, from a cheetah, coyote,or stoat. Early explorers of the American
west ascribed two equally common
names to the mice once their predatory
lifestyles had been recognized —grasshopper mouse in some regions,and scorpion mouse in areas with anabundance of these arachnids. Whilegrasshopper mice eat some plantmaterial, and have been recorded killingand eating lizards, birds, and evenother mice, a significant majority of theirdiet is arthropods including, obviously,
grasshoppers and scorpions (Figure 1).
Are they the only carnivorous
rodents? Actually, no. Indeed, thecommon perception of rodents asprimarily herbivorous is erroneous. Manyrodents are omnivorous and some, likeground squirrels, frequently include

Current Biology 25, R1019–R1031, November 2, 2015 ©2015 Elsevier Ltd All rights reserved

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