150-C 8 APRIL 2022 • VOL 376 ISSUE 6589 science.org SCIENCE
RESEARCH | IN SCIENCE JOURNALS
cause substantial morbidity and
mortality in preterm infants.
However, the drivers of BPD and
BPD-PH are not well understood.
Lao et al. characterized immune
polarization in blood samples
from preterm infants and in
a mouse model of BPD and
BPD-PH. In both cases, BPD was
associated with type 2 immune
polarization, characterized by
interleukin (IL)-4, IL-5, and IL-13,
as well as activation of signal
transducer and activator of
transcription 6 (STAT6). STAT6
deficiency or blockade of type
2 immune mediators partially
reversed evidence of alveolar
and pulmonary vascular disease
in mice, suggesting that this
signaling axis could be targeted
for preterm infants with BPD.
—CSM
Sci. Transl. Med. 14 , eaaz8454 (2022).
CANCER
A PAX8-SOX17 duo in
tumor angiogenesis
The transcription factor PAX8
is essential for the development
of the female reproductive tract
but is frequently amplified in and
supports the growth of ovarian
cancers. By comparing ovar-
ian cancer and nonmalignant
fallopian tube cells and tissues,
Chaves-Moreira et al. found that
PAX8 interacted with another
transcription factor, SOX17,
and that the complex in cancer
cells transcriptionally promoted
a pro-angiogenic secretome.
Repressing the complex
inhibited tumor cell–induced
angiogenesis in both cell culture
and in vivo models. —LKF
Sci. Signal. 15 , eabm2496 (2022).
VIROME
Expanding the
RNA catalog
Apart from their roles in human
infectious diseases, we under-
stand relatively little about
RNA viruses in the wider world.
Recently, the discovery curve
has been spectacular and has
revealed unexpected diversity.
Zayed et al. optimized discovery
and classification methods on
Tara Oceans RNA sequence
data to double the roster of
known RNA virus phyla (see
the Perspective by Labonté
and Campbell). This is not just
a numbers game; the authors
also found a missing link in RNA
virus evolution and discovered
new phyla that dominate in
the oceans and might infect
mitochondria. These viruses
require an ancient enzyme,
RNA-directed RNA polymerase
(RdRp) for replication, which
is thus used as a marker of
deep evolutionary relation-
ships. In addition to the primary
sequence data, information
on the three-dimensional
structures of the RdRp, network-
based clusters, other genomic
domains, and whole-genome
characteristics help to reshape
the outlines of the evolutionary
history of RNA viruses. —CA
Science, abm5847, this issue p. 156;
see also abo5590, p. 138