SCIENCE sciencemag.org 10 APRIL 2020 • VOL 368 ISSUE 6487 151IMAGES: G. KASHGARI
ET AL.
, D E V. C E L L
.^52
, 764 (2020)
selective wetting. Polster et al.
created hydrophobic–hydrophilic
junctions in single nanopores (10
to 140 nanometers in effective
diameter) in silicon nitride mem-
branes. Part of the channel was
lined with a hydrophilic, positively
charged polyelectrolyte, and the
rest with a perfluorinated silane.
These nanopores had a nega-
tive voltage bias threshold for
transporting chloride anions, but
bromide and iodide were trans-
ported at positive bias as well.
Simulations suggested that these
more polarizable anions shed
solvent water more readily and
accumulate on the hydrophobic
walls to induce wetting. —PDS
ACS Nano 10.1021/
acsnano.9b09777 (2020).NEUROSCIENCE
Individual brain networks
A better understanding of how
networks connect in the brain is
important for the personalized
treatment of neurological condi-
tions such as Parkinson’s disease
and psychiatric illnesses such
as Tourette’s syndrome. Circuits
regulating sensorimotor, cogni-
tive, and limbic processes link
the brain’s cortex to subcorticalstructures such as the thalamus.
Greene et al. used functional
magnetic resonance imag-
ing to map the connectivity of
subcortical structures, revealing
variability among individuals.
Somatomotor networks showed
less interindividual variation,
whereas cognitive control net-
works showed more. Integrative
zones included motor, visual,
or cognitive control networks.
Thus, a consensus map of where
pathways are located may not be
precise or helpful for a given indi-
vidual, reflecting the imperfect
success of transcranial magnetic
stimulation and deep-brain
stimulation in the treatment of
depression or essential tremor.
— PJ H
Neuron 105 , 742 (2020).AUTISM
Tau reduction prevents
autism
Autism is a highly prevalent
neurodevelopmental disor-
der associated with impaired
sociality and communication
and repetitive behaviors. So far,
available treatments offer little
benefit. Tai et al. established alink between the neurodegen-
eration-associated protein tau
and autism spectrum disorders
(ASDs). They found that genetic
methods for reducing tau in
two distinct mouse models of
autism alleviated symptoms
ranging from epilepsy to over-
active signaling pathways. Even
partial (~50%) reduction of tau
ameliorated autistic behaviors.
Tau directly interacted with
and inhibited the phosphatase
activity of PTEN, a negative
phosphatidylinositol 3-kinase
(PI3K) regulator, which likely
underlies the beneficial effects
of tau reduction. Thus, tau
regulation of PTEN, and thus
the downstream PI3K–Akt–
mammalian target of rapamycin
pathway, may link multiple ASDs
and potentially provide a target
for therapeutic interventions.
—SMH
Neuron 10.1016/
j.neuron.2020.01.038 (2020).EDUCATION
At the center of
engagement and learning
Moving toward more student-
centric STEM education resultsin an increase in student–
student interactions. Do
these increased peer interac-
tions lead to learning gains?
Williams et al. used network
analysis—specifically, central-
ity, a measurement of how
“central” a particular student
is within the classroom
network—to examine student
interactions in an introduc-
tory physics classroom
using modeling instruction.
Students’ centrality was found
to predict future academic
performance more than prior
grade point average, suggest-
ing that student engagement
is connected to academic
performance. However, this
relationship did not emerge
until the second half of the
semester, suggesting that
the relationship between
engagement and academic
performance, although impor-
tant, is nuanced. Qualitative
methods are recommended
as a follow-up to further
investigate how students
themselves perceive their
engagement in learning com-
munities. —MMc
Phys. Rev. Phys. Educ. Res. 15 ,
020150 (2019).DEVELOPMENTA sticky problem for digits
C
ell death during development is important for finger and toe
separation, but additional developmental programs are also
required for proper digitation. Kashgari et al. show that, after
the death of the mesenchyme cells from which digits form, a
structure called the interdigital epithelial tongue invaginates
into the mesenchyme, allowing the digits to bifurcate. In normal
digit formation, the outermost layer of the embryonic epidermis,
the periderm, prevents digit adhesion. However, after the digits3D reconstructions of two adjacent digits of a mouse showing, on the left,
normal digit separation and, on the right, digit fusion in mutant mouse embryosseparate, they sometimes fuse back together, causing a condition
known as syndactyly. This occurs when the transcription factor
grainyhead-like 3 (GRHL3) is lacking, which results in the usually
nonsticky periderm becoming sticky. —BAP
Dev. Cell. 52 , 764 (2020).