  We present preliminary results from our spectroscopic survey of
low-luminosity early-type galaxies in the Coma cluster conducted with the
Binospec spectrograph at the 6.5~m MMT. From spatially-resolved profiles of
internal kinematics and stellar population properties complemented with
high-resolution images, we placed several low-luminosity dEs on the fundamental
plane in the low-luminosity extension of the available literature data. We also
discovered unusual kpc-sized kinematically-decoupled cores in several dwarf
galaxies, which had been probably formed before these galaxies entered the
cluster.
