Recursive systematic convolutional code (RSC) realization in MATLAB How can I implement $\rm RSC(2,1,2)$ in MATLAB? Can I use convenc function to build RSC? 

The convenc function has 2 arguments: code = convenc(msg,trellis) where trellis=poly2trellis(ConstraintLength,CodeGenerator), and the generator polynomial for this RSC is:
$$
G=\left(1,\frac{1+D^{2}}{1+D+D^{3}}\right)\quad\text{or}\quad G=\left(1,\frac{5}{7}\right)
$$
but for poly2trellis argument CodeGenerator need to be in octal.
The question is already answered but let me structure it for future readers.
From the MATLAB help for the function poly2trellis, here is how you can do it:

TRELLIS = poly2trellis(CONSTRAINTLENGTH, CODEGENERATOR, FEEDBACKCONNECTION)

Hence for the figure in the question:
 RSC_trellis = poly2trellis( 3, [7 5], 7);

Or, for the other possible RSC encoder, i.e. choosing the lower branch to be fedback:
 RSC_trellis = poly2trellis( 3, [7 5], 5);