CR Biologies

Emna Meddeb

Mohamed Charni

Rim Ben Abdallah

Faten Raboudi

Sami Fattouch

A molecular study of Tunisian populations of <i>Dugesia sicula</i> (Plathelminthes, Tricladida) through an identification of a set of genes

Sommaire / Contents

Alexander V. Sirotkin

Andrej Benčo

Milos Mlynček

Abdel H. Harrath

Saleh Alwasel

Jan Kotwica

The involvement of the phosphorylatable and nonphosphorylatable transcription factor CREB-1 in the control of human ovarian cell functions

CV3 - Editorial Board/English

Philippe Grandcolas

Insects: Friends, foes, and models/Insectes : amis, ennemis et modèles / C. R. Biologies 342 (2020) 247–278 251
Fig. 1 A set of insects with a variety of patterns and irides-
cent colors issued from the State Museum of Natural History in
Karlsruhe, Germany (image by H. Zell).
Fig. 2 Chrysina gloriosa, from a macroscopic view to micro-
textures as observed in the green and silver bands.
arranged on a curved surface and, at the mesoscopic scale, it
behaves as an array of wavelength-selective micromirrors [4].
The silver stripe plays the role of a flat metallic reflector oper-
ating over the visible spectrum and into the infrared spectrum
[4]. The orientation of the helicoidal structure varies in green
stripes (Fig. 3), whereas it is fixed in silver stripes.
The outermost part of insect cuticles is very often covered with
wax, which restricts water loss, prevents desiccation, may lend
superhydrophobic and self-cleaning properties to the cuticle,
and serves for chemical communication in many species. While
cuticular waxes are considered isotropic, the wax layer of the
cuticle of C. gloriosa exhibits an intriguing nanoscale laminate
texture, as revealed by electron microscopy of the transverse
sections [5].
Micro-textured cuticles of scarabs may inspire researchers
and engineers to make their replicas as optical materials.
Potential applications are in the field of wavelength-specific
light modulators in routing technologies, broadband reflec-
tors for energy savings, coatings for cryptography purposes
(wavelength-dependent and polarization-dependent micro-
and nanoscale patterns), camouflage (suits with a broad reflec-
tion in the IR spectrum identical to the one of the background)
or thermoregulation for buildings.
Disclosure of interest The author declares that he has no com-
peting interest.
Fig. 3 Transverse view of the cuticle of Chrysina gloriosa in
a green band as seen by transmission electron microscopy. A
typical fingerprint texture is displayed in the chitin network of
the cuticle. The distance between two lines of equal contrast
is related to the pitch of the twisted structure. The helical axis
is perpendicular to the lines. Concave nested arcs are visible
below each polygonal cell. Hypothetical functions are reported:
chemical information (wax layer), optical communication in
the visible and near-infrared spectra, infrared thermoregula-
tion.
References
[1] M. Mitov, Cholesteric liquid crystals in living matter, Soft.
Matter 13 (2017) 4176–4209.
[2] Article in CNRS News at: https://news.cnrs.fr/articles/
natures-liquid-crystals.
[3] M. Mitov, I.C. Khoo (Eds.), Multifunctional reflectors in the
carapace of scarab beetles, Liquid Crystals XXII, SPIE Proc.,
2018 [10735, 10735B].
[4] G. Agez, C. Bayon, M. Mitov, Multiwavelength micromir-
rors in the cuticle of scarab beetle Chrysina gloriosa, Acta
Biomater. 48 (2017) 357–367.
[5] M. Mitov, V. Soldan, S. Balor, Observation of an anisotropic
texture inside the wax layer of insect cuticle, Arthropod
Struct. Dev. 47 (2018) 622–626.
https://doi.org/10.1016/j.crvi.2019.09.005
5
Géopolitique du moustique
Érik Orsenna
Académie française, 23, quai de Conti, 75006 Paris, France
E-mail address: nomade222@orange.fr
Pour l’économiste que je suis, doublé d’un romancier passionné
par les ménages à trois et les meurtres, aucun animal n’est plus
intéressant que le moustique, vieux de 250 millions d’années
et riche d’environ quatre mille espèces.
D’abord, même s’il ne peut voler loin, on le retrouve partout,
d’un bout à l’autre de la planète. Il incarne donc la mondiali-
sation et l’unité de la santé: one health, une bonne santé des
humains n’est possible que si se portent aussi bien les animaux
et les végétaux.
252 Insects: Friends, foes, and models/Insectes : amis, ennemis et modèles / C. R. Biologies 342 (2020) 247–278
Ensuite, aucun serial killer n’est plus efficace: 700 000 morts
par an.
Enfin, sa nuisance ne vient pas de lui, mais des hôtes très per-
nicieux qu’il peut transporter. C’est donc bien un trio qui est à
l’œuvre: un parasite, une femelle moustique qui l’accueille et
l’être humain qu’elle contamine en le piquant pour pomper son
sang. Notons que cette dame n’agit pas ainsi par méchanceté,
mais parce que le sang recueilli contient des protéines néces-
saires au bon développement de ses œufs. En piquant un
humain infecté, elle aspire en même temps le parasite, qui
gagne son estomac, avant, pour notre plus grand malheur, de
gagner ses glandes salivaires: c’est par cette salive qu’il sera
transmis lorsqu’elle piquera un nouvel humain.
La Nature étant, comme l’on sait, sophistiquée, toutes les
espèces de moustiques ne sont pas compétentes pour accueil-
lir tous les virus ou parasites. Par exemple, seuls les Anophèles
transportent Psalmodium falciparum, le responsable du palud-
isme. Et ce sont les Aedes (dont Aedes albopictus, le fameux
« tigre », Fig. 1) qui portent les virus de la dengue, du Zika et du
chikungunya.
Depuis quelques décennies, un double mouvement se dessine.
Le premier est une invasion, l’invasion par nous, les humains,
des habitats animaux. Pour accroître la superficie de nos villes
et de nos champs, nous défrichons, nous avançons dans les
profondeurs des forêts, domaine jusque-là réservé aux bêtes,
petites ou grandes. Il en résulte des épidémies parfois très
graves, comme celles du sida ou de la maladie à virus Ebola.
Car les virus, jadis isolés, sortent de ces zones forestières peu
habitées et se propagent sans frontières.
L’autre mouvement est celui de l’adaptation. Les moustiques
voient en nous de merveilleux repas de sang. Dans ces con-
ditions, pourquoi s’obstiner à piquer la nuit des êtres trop
souvent protégés par des moustiquaires, alors qu’en plein jour
ces mêmes réservoirs de sang se retrouvent sans défense? Et
pourquoi demeurer dans la jungle, alors que les repas de sang
s’accumulent dans les villes? C’est ainsi que les espèces noc-
turnes deviennent diurnes, les forestières, urbaines.
Comment lutter?
D’abord, ainsi que vous le suggère le bon sens, empêcher
les moustiques de se multiplier en supprimant les « gites
larvaires », ces eaux stagnantes où ils naissent et passent
la première partie de leur vie. Ensuite, éviter de se faire
piquer. La prévention, comme chacun sait, est la meilleure
des médecines. Un programme massif de moustiquaires
imprégnées d’insecticide a permis de réduire de moitié le nom-
bre de morts du paludisme.
Des médicaments existent pour contrer les malfaisances du
parasite une fois qu’il nous a infectés. Ainsi, la « poudre des
Jésuites », la future quinine, et l’artémisinine, extraite d’une
plante bien connue de la vieille pharmacopée chinoise. Mal-
gré la combinaison de plusieurs molécules, les phénomènes de
résistance se multiplient, notamment dans l’Est du Cambodge,
une zone où, par chance, la prévalence, c’est-à-dire le nom-
Fig. 1 Moustique tigre - Crédit photo: PHANIE.
bre de personnes atteintes sur une période donnée, reste peu
élevée. De telles résistances en Afrique, plus peuplée et plus
touchée, auraient des conséquences dramatiques.
Ces limites de l’efficacité des médicaments et les difficultés
extrêmes rencontrées pour fabriquer des vaccins ont ouvert
la voie à d’autres méthodes plus radicales. Par exemple, le
lâcher de mâles préalablement rendus stériles dans une zone
de moustiques sauvages. Ou l’utilisation de ciseaux molécu-
laires, le fameux CRISPR-Cas 9, capables de supprimer des gènes
indésirables, mais aussi d’en insérer de nouveaux, comme celui
d’une résistance au paludisme.
Plus fou encore, le forçage génétique, en anglais gene drive, per-
met à une modification génétique réalisée grâce aux ciseaux
moléculaires CRIPR-Cas 9 d’être transmise de façon quasi cer-
taine de génération en génération. C’est ainsi que l’on pourrait
génétiquement programmer l’extinction complète et défini-
tive des moustiques. Certains, rappelant le nombre de décès
causés par ces jolis insectes, y sont déterminés. D’autres sont
beaucoup plus prudents, rappelant leur rôle essentiel dans la
chaîne alimentaire et dans la pollinisation. Ils se demandent
aussi quels « hôtes » les parasites choisiraient si leurs trans-
porteurs habituels disparaissaient. Quant aux manipulations
génétiques, leur sécurité n’est pas encore garantie.
Non scientifique, mais économiste, je voulais continuer mon
travail sur la mondialisation en abordant la santé. Grâce au
docteur de Saint-Aubin, et bien sûr à des dizaines d’experts,
à commencer par mon enseignante en cheffe Anna-Bella Fail-
loux, j’ai pu écrire cette « géopolitique des moustiques ». Qui
confirme, s’il en était besoin, l’unité fondamentale de notre
planète. One health. La vie ne connaît pas de frontières, ni géo-
graphiques, ni entre les règnes.
Déclaration de liens d’intérêts L’auteur déclare qu’il n’a pas de
liens d’intérêts.
https://doi.org/10.1016/j.crvi.2019.09.006
Session II. Diversity, diversification,
extinction
6
The origin of diversity in
insects: Speciation, adaptation
and the Earth dynamics
Philippe Grandcolas
Institut de systématique, évolution, biodiversité (ISYEB),
Muséum national d’histoire naturelle, CNRS, Sorbonne
Université, Paris, France
E-mail address: pg@mnhn.fr
The diversity of insects is often explained as a product of major
radiations, triggered by remarkable adaptations that allowed
them to exploit different environments and to accompany the
rise of flowering plants. A significant part of insect diversity
results however from allopatric speciation with niche con-
servatism that exposed species to different conditions and
stimulated adaptive divergence. We demonstrated that for sev-
eral groups of Insects (cockroaches, crickets and grasshoppers)
in the island of New Caledonia.
Since Darwin and Wallace, islands are considered as labo-
ratories of evolution, being closed systems of manageable
size. New Caledonia is especially interesting in this respect,
according to unique characteristics. Being the oldest oceanic
island in the world and quite isolated from continents, bio-
logical evolution occurred there in situ during long periods.
As a tropical and medium-sized island harboring a very rich
biodiversity, it also offered facilities to study many different
evolutionary questions. New Caledonia (hereafter NC) has thus
the best characteristics as a model system, allowing testing
very diverse evolutionary assumptions with limited efforts


The origin of diversity in insects: Speciation, adaptation and the Earth dynamics

Xavier Bellés

Insects: Friends, foes, and models/Insectes : amis, ennemis et modèles / C. R. Biologies 342 (2020) 247–278 253
and infrastructures. Unfortunately, these amazing geograph-
ical characteristics have also constrained the scientific study
of NC until now, especially because of its isolation from large
academic centers.
Establishing NC as a modern oceanic model system resulted
however from our work, later than the 1990s. Before, NC had
the reputation of an amazingly old Gondwanan place and was
intuitively considered as a continental fragment. If so, its use-
fulness as a model system to study evolution would have been
limited since the biota of continental islands (e.g., Madagascar
or New Zealand) are a complicated mix of organisms dating
back to the separation with neighboring continental territories
or having colonized the island by dispersal. In most of these
cases, it happened difficult to distinguish between both these
different components and to examine evolutionary assump-
tions that require a reference dating point. The reasons why NC
was traditionally considered a continental territory were the
age of its deep geological basement and the local occurrence
of relict species. In agreement with this common assump-
tion, the NC geological deep basement is ancient and predates
Gondwanan breakup. But this basement has been submitted to
important environmental disturbances because of the island
location at the limit between two tectonic plates. Actually, the
island has been submerged twice for a long time at Paleocene
and Eocene epochs and only emerged around 37 ± 3 Ma.
This geological background was in need of independent test-
ing with biological studies. We thus built multiple molecular
phylogenetic trees of different groups of organisms, dated with
probabilistic methods and external calibration points. A first
review [1] and a more recent meta-analysis [2] of these stud-
ies showed that most groups colonized NC and diversified just
after 37 My, confirming the geological scenario of recent terres-
trial emergence. However, a few local species belong to groups
that were dated much older than 37 My, representing true
relicts, i.e. recent species that remained from old clades [3].
These old clades can only be assumed to have been ancestrally
present in the region, colonizing NC after its emergence and
going extinct in other territories, either drowned islands or
mutated continental ecosystems.
These different results strongly indicated that NC is an oceanic
island, even if very old–actually the oldest one in the world–and
that its local biota dated back to island emergence. Relicts are
fascinating species, unfortunately too sparsely known after the
major extinction of their relatives to support any robust biogeo-
graphic scenario. Fossil data are absolutely needed to assess the
evolutionary history of these taxa without speculation.
Setting up this biogeographic scenery has allowed one to
properly conduct speciation studies by inferring the age and
the ancestral phenotypic characters of local lineages. We did
that in several groups of insects, cockroaches, crickets, and
grasshoppers, and we showed that speciation occurred mainly
in relation to orography, in allopatry and with niche conser-
vatism. Closely related species occurred as narrow endemics
in the same habitats of neighboring areas, mainly on adjacent
small mountains. Sympatry, when observed, was inferred to
be secondarily caused by the increase of distribution area of
older species. Even if most speciation events seemed to have
occurred without any important evolutionary change, some
adaptive shifts have been detected in several cases, from dif-
ferent food plants on metalliferous soils to different habitats in
the forest understory. The major conclusion that can be drawn
from high speciation rate and narrow endemicity in New Cale-
donia is that speciation went before, not always together with
adaptive divergence. Here we offer both a new and powerful
natural laboratory of evolution, calibrated in space and time,
and a model of speciation where niche conservatism is the
engine for adaptive divergence.
Disclosure of interest The author declares that he has no com-
peting interest.
References
[1] P. Grandcolas, J. Murienne, T. Robillard, L. Desutter-
Grandcolas, H. Jourdan, E. Guilbert, et al., New Caledonia:
a very old Darwinian island? Philos. Trans. R. Soc. Lond. B
Biol. Sci. 363 (2008) 3309–3317.
[2] R. Nattier, R. Pellens, T. Robillard, H. Jourdan, F. Legendre, M.
Caesar, et al., Updating the Phylogenetic Dating of New Cale-
donian Biodiversity with a Meta-analysis of the Available
Evidence, Sci. Rep. 7 (2017) 3705.
[3] P. Grandcolas, R. Nattier, S.A. Trewick, Relict species: a relict
concept? Trends Ecol. Evol. 29 (2014) 655–663.
https://doi.org/10.1016/j.crvi.2019.09.007
7
A glance at the deep past history
of insects
André Nel
Institut de systématique, évolution, biodiversité, ISYEB, UMR
7205, CNRS, MNHN, UPMC, EPHE, Muséum national d’histoire
naturelle, Université des Antilles, Sorbonne Université, CP 50,
Entomologie, 57, rue Cuvier, 75005 Paris, France
E-mail address: andre.nel@mnhn.fr, anel@mnhn.fr
With more than 1,100,000 described species, the insects are
the most diverse clade of extant animals, far before all other
groups. Nevertheless, they undergo a drastic decrease of their
populations, due to the sixth extinction of human origin. Thus
it is important to define when and how they became so diverse
and if they were impacted by the major crises of biodiversity
in the deep past to estimate the importance of the current one.
Insects are generally among the best preserved terrestrial fos-
sil organisms, much more complete than the vertebrates. They
are also much more frequent. Thousands can be found in
Konservat-Lagerstätten since the Carboniferous. They are pre-
served either in lacustrine sediments as compression fossils, or
embedded in amber (fossil resins) (Fig. 1).
The Hexapoda (or six-legged arthropods, viz., wingless Collem-
bola, Diplura, Protura ; wingless and winged Insecta) are among
the oldest known terrestrial organisms, with first records dated
from the Middle Devonian of Rhynie in Scotland. Recent molec-
ular phylogenetic dating suggests that they appeared during
the Silurian or even the Ordovician, with the first terrestrial
plants. The Devonian hexapodan record is very scarce and dis-
appointing, with less than six described fossils, all wingless [1].
Fig. 1 A. Compression fossil, Orthoptera, Middle Permian
(China). B. Amber inclusion, Hymenoptera Bethylidae, earliest
Eocene (France). Scale bars: 10 mm (A), 1 mm (B).
A. Fossile en compression, Orthoptera, Permien moyen (Chine).
B. Fossile dans de l’ambre, Hymenoptera Bethylidae, Éocène basal
(France). Échelles: 10 mm (A), 1 mm (B).
254 Insects: Friends, foes, and models/Insectes : amis, ennemis et modèles / C. R. Biologies 342 (2020) 247–278
The early Carboniferous one is even worse, without any fos-
sil insects. But at the very end of this period and during the
late Carboniferous, the insect diversity exploded, with a ‘sud-
den appearance’ of winged insects with very diverse feeding
resources, e.g., carnivorous, plant suckers, leaf eaters, detritivo-
rous, gall-makers, etc. The wingless clades remained a minority
and the high diversification of the Carboniferous Hexapoda
clearly concerned the winged forms. Wings and flight were
probably the first crucial structures and function that allowed
the first burst of diversification of the insects. Flight allows
them to escape predators, find new resources, sexual partners,
and travel to new environments. The most popular fossil insects
are the Paleozoic ‘giant’ dragonflies Meganeuridae. These fly-
ing insects with very large wingspans (ca. 70 cm wide) had
large bodies but comparable to those of some extant beetles.
In fact, the unique really giant Carboniferous terrestrial arthro-
pod was Arthropleura, a myriapod that was more than 1 m long.
It is supposed that the great increase of oxygen proportion in
the air during the Late Carboniferous favored the gigantism
among the terrestrial arthropods, due to their breathing via tra-
chea. The question is in fact more complex, because the winged
insects knew a unique situation during the late Paleozoic, as
they had no flying vertebrates as predators. As they were the
only flying animals, they probably knew a phenomenon of par-
allel increases of sizes of predators (the Meganeuridae) and
preys, the Palaeodictyoptera that also became larger and larger
[2]. At the end of the middle Permian, both clades are very
diverse, with still very large taxa, while the oxygen proportion
began to decrease. The first gliding ‘lizard-like’ vertebrates are
also recorded at the same time, and certainly began to pre-
date these giant insects, which became rarer during the late
Permian and no longer existed in the Triassic. The late Carbonif-
erous was also the time of the oldest known holometabolous
insects, with complete metamorphosis (wasps, beetles, scor-
pionflies), and of the oldest bugs (Hemiptera). These were
discovered very recently because they were very small insects
[3]. They are now the most diverse animal clades, with the
‘big five’ (Hemiptera, Hymenoptera, Diptera, Lepidoptera, and
Coleoptera). But during all the Paleozoic, these insects were
clearly very few. Holometaboly in itself was not ‘sufficient’
to cause their diversification and each of these orders ‘sepa-
rately’ diversified during the last 220 Ma. The exact impact on
the insects of the most important Permian–Triassic crisis of
diversity remains difficult to estimate because there are very
few latest Permian and earliest Triassic outcrops with insects.
Thus if we know that the Triassic entomofaunas are very differ-
ent from the Permian ones, we cannot establish that the great
changes that occurred between the two periods happened dur-
ing this crisis or before, during the late Permian or even at
the end of the middle Permian. Nevertheless, the Palaeodic-
tyoptera and the Meganisoptera are no longer present in the
Triassic, while all the Triassic entomofaunas are clearly ‘domi-
nated’ by the beetles and other Holometabola. Beetles were still
minority during all the Permian in the fossil record. The ‘true’
flies (Diptera) and crown group of Hymenoptera are also dated
from the Middle Triassic. At the end of this period, all the extant
orders were present, except, maybe the parasite groups such as
fleas (Siphonaptera), whose oldest fossils are middle Jurassic.
The ‘modern’ entomofauna is thus much older than the extant
mammal orders. During the Jurassic, the insects continued
their diversification, with the first parasitoid wasps (there is no
record of parasitoid insects before). The Cretaceous was the sec-
ond crucial period for the insect (especially the Holometabola)
diversification, with the oldest eusocial taxa (termites, wasps,
bees, ants). The Albian–Cenomanian (ca. 100 Ma.) was the time
of replacement of the gymnosperms by the angiosperms in all
the terrestrial biotas, and the time of appearance of nearly all
the extant insect families (even some extant genera have this
age). It is also an important time of extinctions of several older
Jurassic clades, replaced by extant taxa. Only the insects that
adapted to the new environments related to flowering plants
could diversify. The modern insect–plant relationships were
established during the late Cretaceous. The recent new studies
of the extraordinarily rich and diverse entomofauna of the ‘mid’
Cretaceous Burmese amber allowed one to discover that the
Cretaceous insect world was as complex, rich and diverse as the
extant one. The Cretaceous–Cenozoic (K–T) crisis had clearly
a very weak impact on insect diversity, at least at the family
level [4]. In fact, there were more extinctions and appear-
ances of new families during the Paleocene–early Eocene than
during the K–T crisis. These were periods of global warming
followed by global cooling. The entomofaunas suffered the
successive periods of cooling of the Oligocene, Miocene, and
the Pliocene–Pleistocene glaciations, causing the extinctions
of numerous widespread families that survived in small areas
(the Australian mastotermitid termites or the Tasmanian hairy
cicadid Tettigarctidae are the most spectacular examples).
The deep past history of insects is unique, with bursts of diver-
sification ca. 330 Ma, 220 Ma, and 100 Ma ago. The causes of
the first one remain poorly known, those of the second one are
probably linked to the renewal of the ecosystems during the
early Triassic, and the third one to the great floristic change. At
least the K–T crisis did not affect much insect diversity. Thus
the current crisis of biodiversity that begins to greatly affect the
insect biomass, is extremely alarming. It may be more impor-
tant than the K–T one.
Disclosure of interest The author declares that he has no com-
peting interest.
References
[1] R. Garrouste, G. Clément, P. Nel, M.S. Engel, P. Grandcolas,
C. D’Haese, et al., A complete insect from the Late Devonian
period, Nature 488 (2012) 82–85.
[2] A. Nel, J. Prokop, M. Pecharová, M.S. Engel, R. Garrouste,
Palaeozoic giant dragonflies were hawker predators, Sci.
Rep. 8 (12141) (2018) 1–5.
[3] A. Nel, P. Roques, P. Nel, A.A. Prokin, T. Bourgoin, J. Prokop,
et al., The earliest known holometabolous insects, Nature
503 (2013) 257–261.
[4] P. Nel, S. Bertrand, A. Nel, Diversification of insects since the
Devonian: a new approach based on morphological dispar-
ity of mouthparts, Sci. Rep. 8 (3516) (2018) 1–45.
https://doi.org/10.1016/j.crvi.2019.09.008
8
The metamorphosis of insects
and their regulation
Xavier Bellés
Institute of Evolutionary Biology, CSIC–Universitat Pompeu Fabr,
Barcelona, Spain
E-mail address: xavier.belles@ibe.upf-csic.es
Metamorphosis was a key innovation in insect evolution,
wherein the individual acquires characteristic adult features
and stops molting during postembryonic development. The
ancestral metamorphosis mode was hemimetaboly, in which
the embryogenesis gives rise to a first instar nymph with the
essential adult body structure. The nymphs grow gradually
and the final molt to the adult stage completes the formation
of functional genitalia and wings. The metamorphosis mode
known as holometaboly emerged from hemimetaboly, which
is characterized by embryogenesis that produces a larva with
a body form that may be substantially different from that of
the adult. The larva grows through various stages until molt-
ing to the pupal stage, which bridges the gap between the
morphologically divergent larva and that of the winged and
reproductively competent adult. In the hemimetabolan and
holometabolan modes, metamorphosis is regulated by two
hormones: the juvenile hormone (JH) and the ecdysone, plus
its biologically active derivative, 20-hydroxyecdysone (20E).
20E is a steroid, and its main role is to promote the succes-
sive molts, including the metamorphic one, whereas JH is a
terpenoid, whose function is to repress metamorphosis [1]. The
action of these hormones is underpinned by the mechanisms
that transduce the hormonal signal through a pathway of gene
activation. The 20E signaling pathway was first described in
the 1990s [2], whereas the most important details of the JH
pathway were unveiled recently. Important components of the
JH signaling pathway are the JH receptor, which is the basic


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A molecular study of Tunisian populations of <i>Dugesia sicula</i> (Plathelminthes, Tricladida) through an identification of a set of genes

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The involvement of the phosphorylatable and nonphosphorylatable transcription factor CREB-1 in the control of human ovarian cell functions

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