Sequence alignment between 4u3f(J) and UniProt seq F1NC51 (F1NC51_CHICK):

F1NC51 (F1NC51_CHICK): Complex III subunit 9 from Gallus gallus 
                 10        20        30        40        50        60  
         ---------+---------+---------+---------+---------+---------+--
UniProt: MALLRQAYSALFRRTSTFALTVVLGAVLFERAFDQGADAIFEHLNEGKLWKHIKHKYEASEE
PDB seq: -ALLRQAYSALFRRTSTFALTVVLGAVLFERAFDQGADAIFEHLNEGKLWKHIKHKYEASEE
          ------+---------+---------+---------+---------+---------+----
               10        20        30        40        50        60