SMN regulates axonal local translation via miR-183/mTOR pathway.

Reduced expression of SMN protein causes spinal muscular atrophy (SMA), a neurodegenerative disorder leading to motor neuron dysfunction and loss. However, the molecular mechanisms by which SMN regulates neuronal dysfunction are not fully understood. Here, we report that reduced SMN protein level alters miRNA expression and distribution in neurons.

Interaction of survival of motor neuron (SMN) and HuD proteins with mRNA cpg15 rescues motor neuron axonal deficits.

Spinal muscular atrophy (SMA), caused by the deletion of the SMN1 gene, is the leading genetic cause of infant mortality. SMN protein is present at high levels in both axons and growth cones, and loss of its function disrupts axonal extension and pathfinding. SMN is known to associate with the RNA-binding protein hnRNP-R, and together they are responsible for the transport and/or local translation of β-actin mRNA in the growth cones of motor neurons.

Phosphoproteomics.

Current analytical protein methods show phosphorylation to be the most ubiquitous, evolutionary conserved post-translational modification Post-Translational Modification (PTM). The reversible and transient nature of protein phosphorylation allows signal transduction pathways to carry out diverse cellular functions. From bacteria to humans, phosphorylation serves to modify protein function by altering protein stability, cellular location, substrate affinity, complex formation, and activity; thus allowing essential events such as cell cycle and growth to occur at precise times and locations.

Ribosomal s6 kinase cooperates with casein kinase 2 to modulate the Drosophila circadian molecular oscillator.

There is a universal requirement for post-translational regulatory mechanisms in circadian clock systems. Previous work in Drosophila has identified several kinases, phosphatases, and an E3 ligase that are critical for determining the nuclear translocation and/or stability of clock proteins. The present study evaluated the function of p90 ribosomal S6 kinase (RSK) in the Drosophila circadian system.

Genetic and biochemical strategies for identifying Drosophila genes that function in circadian control.

Explicit biochemical models have been elaborated for the circadian oscillators of cyanobacterial, fungal, insect, and mammalian species. In contrast, much remains to be learned about how such circadian oscillators regulate rhythmic physiological processes. This article summarizes contemporary genetic and biochemical strategies that are useful for identifying gene products that have a role in circadian control.