How do SMA-linked mutations of SMN1 lead to structural/functional deficiency of the SMA protein?
Fig 3
Disruptions of local electrostatic interactions by three SMA-linked missense mutations.
In this figure, the electrostatic interaction disruptions for D44V, E134K and Q136E are illustrated in the upper, the middle and the lower panels, respectively. In the three panels, the negative (partial, for hydrogen bond acceptor group) charge is represented with a red circle with a minus sign inside, the positive (partial, for hydrogen bond donor group) charge is represented with a blue circle with a plus sign inside, the salt bridge/the hydrogen bond is represented with a set of green squares, representing electrostatic attraction. For the upper panel, the impact of the mutation is represented with the disappearance of the green squares on the right side, representing the disappearance of the Asp44-Arg213 salt bridge. For the middle and lower panels, the impacts of the mutations are represented with a set of red squares, representing electrostatic repulsion.