Development and repair of blood vessels in the zebrafish spinal cord.

The vascular system is inefficiently repaired after spinal cord injury (SCI) in mammals, resulting in secondary tissue damage and immune deregulation that contribute to the limited functional recovery. Unlike mammals, zebrafish can repair the spinal cord (SC) and restore motility, but the vascular response to injury has not been investigated. Here, we describe the zebrafish SC blood vasculature, starting in development with the initial vessel ingression in a body size-dependent manner, the acquisition of perivascular support and the establishment of ventral to dorsal blood circulation.

It's a two-way street: Photoswitching and reversible changes of the protein matrix in photoswitchable fluorescent proteins and bacteriophytochromes.

Chromophore-bearing proteins that are (reversibly) altered after light illumination are major functional components of nature. They gained considerable attention in the last decades since the dynamic interactions of the chromophore and protein matrix can be used to control downstream effects altering the functionality of proteins, cells, or complete organisms with light (optogenetics). Additionally, the photophysical effects can be employed to add capabilities to optical imaging.

APC couples neuronal mRNAs to multiple kinesins, EB1, and shrinking microtubule ends for bidirectional mRNA motility.

Understanding where in the cytoplasm mRNAs are translated is increasingly recognized as being as important as knowing the timing and level of protein expression. mRNAs are localized via active motor-driven transport along microtubules (MTs) but the underlying essential factors and dynamic interactions are largely unknown. Using biochemical in vitro reconstitutions with purified mammalian proteins, multicolor TIRF-microscopy, and interaction kinetics measurements, we show that adenomatous polyposis coli (APC) enables kinesin-1- and kinesin-2-based mRNA transport, and that APC is an ideal adaptor for long-range mRNA transport as it forms highly stable complexes with 3'UTR fragments of several neuronal mRNAs (APC-RNPs).

Mammalian Neuronal mRNA Transport Complexes: The Few Knowns and the Many Unknowns.

Hundreds of messenger RNAs (mRNAs) are transported into neurites to provide templates for the assembly of local protein networks. These networks enable a neuron to configure different cellular domains for specialized functions. According to current evidence, mRNAs are mostly transported in rather small packages of one to three copies, rarely containing different transcripts.