(= carboxy-terminal domain) Protein domain unique to Pol-II that contains multiple repeats of the YSPTSPS sequence. The CTD plays an important part in organizing the various protein factors that make up the RNA-processing â€˜factory` that regulates the processing of the 3&` end of mRNAs made by Pol-II.
[instrument] A CTD or Sonde is an oceanography instrument used to determine the conductivity, temperature, and depth of the ocean. The CTD may be incorporated into an array of Niskin bottles referred to as a carousel or rosette. The sampling bottles close at predefined depths, triggered either manually or by a computer, and the water sample... Found on http://en.wikipedia.org/wiki/CTD_(instrument)