Significance: Influenza A virus (IAV) is one of the most important human pathogens, and it is crucial to understand its life cycle to develop antiviral strategies. However, IAV uncoating, an essential step in viral infection, has remained incomprehensible. Here, via the construction of infectious IAV virions encapsulating quantum dots, we tracked the uncoating and viral ribonucleoprotein complex (vRNP) dynamics of single IAV virions. Our results reveal that after viral fusion and uncoating, IAV vRNP segments are released separately into the cytosol, and individual vRNPs undergo a three-stage active nuclear import process and display two diffusion patterns within the nucleus. These findings reveal uncoating and vRNP trafficking mechanisms which may assist in developing new strategies to block IAV infection.

Illumination of biological events with near‐infrared II sub‐channel (NIR‐IIb, 1500–1700 nm) enhances the transparency of biological tissues, which is very attractive for deep imaging. Due to the long‐wavelength, which reduces optical damage, suppresses autofluorescence, and obviates light scattering, NIR‐IIb nanoprobes afford deep tissue penetration with unprecedented spatiotemporal resolution. Hence, NIR‐IIb imaging facilitates deep learning and decipherment of biological proceedings in living organisms with astounding high clarity. In comparison to its predecessors in the visible‐near‐infrared spectrum, imaging in the NIR‐IIb has shown great potential for tissue imaging and extrapolating imaging applications for clinical studies. However, the use of organic fluorescent nanoprobes (OFNPs) in the NIR‐IIb region is still rare since it is in its early stages. Thus, herein we aim to survey the recent development of different organic fluorescent nanomaterials with NIR‐IIb characteristics, their unique photophysical properties, and their utilization in deep imaging in animal models. Further, practical researches on organic fluorescent nanoprobes with NIR‐IIb emission and their transition to clinical applications are highlighted.