Carrier proteins articles from across Nature Portfolio

A unique soluble β-carotene-binding protein pigment extracted from yellow locust cuticle is biochemically and spectroscopically equivalent to the protein reconstituted in carotenoid-producing E. coli cells and capable of binding to chitin in vitro.

Monoamines and neurotoxicants share a binding pocket in VMAT1 featuring polar sites for specificity and a wrist-and-fist shape for versatility, and monoamine enrichment in storage vesicles arises from dominant import via favoured lumenal-open transition of VMAT1 and protonation-precluded binding during its cytoplasmic-open transition.

Anion exchanger 2 (AE2), a widely expressed Cl- /HCO3 - exchanger, participates in the regulation of intracellular pH. Here, the authors present the structures of AE2 and uncover the regulatory mechanism of PIP2.

The serotonin transporter, targeted by several medications, terminates neurotransmission by clearing serotonin from the synaptic cleft. Combining biochemical results with in silico data, the authors show the key interactions that initiate substrate transport.

BTR1 is an electrogenic H+ transporter belonging to the bicarbonate transporter family. Here, the authors present structures of BTR1 in different conformations and uncover PIP2 as the activator of BTR1.

Concentrative nucleoside transporters (CNTs) are cellular nucleoside influx systems, but their in vivo roles are poorly defined. By generating CNT1 knockout (KO) mice, here the authors show a role of CNT1 in the renal reabsorption of endogenous and synthetic nucleosides.

Peptidoglycan recognition proteins (PGRPs) are a key part of the innate immune system's defense against bacteria. PGRPs are now shown to act through a conserved secretion stress–sensing two-component system, which leads to membrane depolarization and the release of cytotoxic hydroxyl radicals. Thus, PGRPs exploit an ancient bacterial stress response to elicit cell death, and this pathway may be targeted to produce improved antimicrobial drugs (pages 676–683).

Enhancer sequences increase gene transcription with the help of a co-activator complex, the Mediator. Another protein complex — cohesin — seems to work with Mediator to bring together enhancers and promoters. See Article p. 430

The signaling intermediates that activate inflammasomes are elusive. New data now show that reactive oxygen species causes TXNIP to associate with NLRP3 and activate the inflammasome.