Science - USA (2021-12-24)

1574 24 DECEMBER 2021 • VOL 374 ISSUE 6575 science.org SCIENCE

RESEARCH | IN OTHER JOURNALS

HIV-positive individuals who go
on ART shortly after infection
reconstitute their cutaneous TR
cells within a year. Thus, early
diagnosis and treatment of HIV
infection may help to stave off
HPV-related cancers. —STS
Immunity 10.1016/
j.immuni.2021.10.021 (2021).

CANCER

A new cancer target?
Therapeutic treatments for
metastatic cancer are an
important unmet need. Studies
have shown that the interaction
between metadherin (MTDH)
and staphylococcal nuclease
domain-containing (1SND1) is
important in tumor initiation,
progression, and metastasis
in mice. Shen et al. show that
deletion of the Mtdh gene in
established mammary tumors
in mice suppressed tumor
development, reduced metas-
tasis, and improved survival.
This effect was dependent on
their interaction with SND1. The
authors also found compounds
that could disrupt the interac-
tion by binding to SND1. Their
lead molecule reduces tumor
growth and lung metastasis in
established mammary tumors
in vivo. Preventing the MTDH–
SND1 interaction also sensitizes

mammary tumors to chemo-

therapy. This indicates that

interfering with this protein-

protein interaction could be

a viable strategy for clinical

investigation. —GKA

Nat. Cancer 10.1038/

s43018-021-00279-5 (2021).

POROUS FRAMEWORKS

Chalcogen-bonded

organic frameworks

The assembly of porous supra-

molecular organic frameworks

is often achieved by designing

hydrogen-bonding interactions,

but the use of other noncova-

lent interactions could expand

the types of materials that

could be synthesized. Eckstein

et al. derivatized the ends of

the propeller-shaped mol-

ecule triptycene with aromatic

rings containing selenium and

nitrogen atoms to form tripty-

cene tris(1,2,5-selenadiazole).

In nonpolar solvents, this

molecule assembles through

nitrogen lone-pair electrons

donating into selenium s holes.

The resulting antiparallel

motifs form ~2-nanometer-

diameter hexagonal channels.

These frameworks can

undergo host-guest exchange,

such as replacing

1,2,5-trichlorobenzene with

1-chloronaphthalene. The

topology of the frameworks

is sensitive to solvent , and

the one grown from 1-chloro-

naphthalene was altered after

exposure to carbon tetrachlo-

ride vapor. —PDS

J. Am. Chem. Soc. 143 , 20207 (2021).

MACHINE LEARNING

Learning about new

classes of antibiotics

Machine learning (ML) is

increasingly being used as

an advisory tool to guide

antibacterial drug searches.

Such methods typically use

large training datasets and

require extensive prior study

of structure-activity relation-

ships. ML models have proven

to be effective within previously

studied classes of antibiot-

ics, but their predictive power

is significantly limited when

the task is to find candidate

molecules that do not resemble

known antibiotics. Tiihonen

et al. present a general ML

framework that does not rely

on prior knowledge of the

mechanism of antibiotic action.

Their ML model developed

for conjugated oligoelectro-

lyte molecules successfully

predicted their antimicrobial

activity against E. coli K12 and

could potentially be applied to

other understudied antibiotic

classes. —YS

J. Am. Chem. Soc. 10.1021/

jacs.1c05055 (2021).

P H OTOVO LTA I CS

A solar cell doubling up

as a battery

Solar power is hampered by

daily and seasonal fluctuations

of power output. This inconsis-

tency can be compensated for

by using energy storage such

as rechargeable batteries but

will increase the total cost and

decrease the overall efficiency

of the system. Jiang et al. devel-

oped a solar-powered battery in

which the coexistence of photo-

electric conversion and storage

in a single device is achieved

for the first time. The device

consists of a van der Waals het-

erojunction between a tungsten

diselenide layer and a quasi–

two-dimensional electron

gas, has an external quantum

efficiency of more than 90%,

and can retain its charge for

up to 7 days, but requires the

liquid nitrogen temperature to

be functional. —YY

Phys. Rev. Lett. 127 , 2 174 0 1 (2021). PHOTO: ALEXIS LLORET/ALAMY STOCK PHOTO

New techniques may help agriculture facilities, such as this

large-scale egg farm, obtain animals of a single sex without culling.

GENETICS

Single-sex offspring

A

griculture and research practices often favor one

sex over the other. For egg production, female

chickens are needed, whereas for beef production,

males are preferred. To eliminate the need to cull

animals, methods are being explored to reliably

generate single-sex populations. Douglas et al. suc-

ceeded in this goal by using a CRISPR-Cas9 strategy

to efficiently produce only male or female mice. When

males carrying a Cas9-encoding transgene on either

the X or Y chromosome are mated with females with a

guide RNA that targets the topoisomerase 1 gene, only

one sex survives to birth. It is likely that this method can

be applied to other vertebrate species. Although this

technique solves the ethical issues associated with the

culling of unwanted livestock, it could introduce other

ethical concerns. —BAP Nat. Commun. 12 , 6926 (2021).