title: Remove all text before colon
body: <p>I have a file containing a certain number of lines. Each line looks like this:</p>
  
  <pre class="lang-none prettyprint-override"><code>TF_list_to_test10004/Nus_k0.345_t0.1_e0.1.adj:PKMYT1
  </code></pre>
  
  <p>I would like to remove all before ":" character in order  to retain only PKMYT1 that is a gene name. 
  Since I'm not an expert in regex scripting can anyone help me to do this using Unix (sed or awk) or in R?</p>