Small near-infrared photochromic protein for photoacoustic multi-contrast imaging and detection of protein interactions in vivo.

TitleSmall near-infrared photochromic protein for photoacoustic multi-contrast imaging and detection of protein interactions in vivo.
Publication TypeJournal Article
Year of Publication2018
AuthorsL Li, AA Shemetov, M Baloban, P Hu, L Zhu, DM Shcherbakova, R Zhang, J Shi, J Yao, LV Wang, and VV Verkhusha
JournalNature communications
Volume9
Issue1
Start Page2734
Date Published07/2018
Abstract

Photoacoustic (PA) computed tomography (PACT) benefits from genetically encoded probes with photochromic behavior, which dramatically increase detection sensitivity and specificity through photoswitching and differential imaging. Starting with a DrBphP bacterial phytochrome, we have engineered a near-infrared photochromic probe, DrBphP-PCM, which is superior to the full-length RpBphP1 phytochrome previously used in differential PACT. DrBphP-PCM has a smaller size, better folding, and higher photoswitching contrast. We have imaged both DrBphP-PCM and RpBphP1 simultaneously on the basis of their unique signal decay characteristics, using a reversibly switchable single-impulse panoramic PACT (RS-SIP-PACT) with a single wavelength excitation. The simple structural organization of DrBphP-PCM allows engineering a bimolecular PA complementation reporter, a split version of DrBphP-PCM, termed DrSplit. DrSplit enables PA detection of protein-protein interactions in deep-seated mouse tumors and livers, achieving 125-µm spatial resolution and 530-cell sensitivity in vivo. The combination of RS-SIP-PACT with DrBphP-PCM and DrSplit holds great potential for noninvasive multi-contrast deep-tissue functional imaging.

DOI10.1038/s41467-018-05231-3
Short TitleNature communications