Alternative transcription and two modes of splicing result in two myosin light chains from one gene

Abstract
Chicken skeletal muscle myosin alkali L chains are encoded by a single gene of size 18 kilobases (kb). This gene has 2 transcription initiation sites from which 17.5- and 8-kb precursor RNA are transcribed. These RNA are processed by different modes of splicing to form mRNA encoding distinct L chain (LC1 and LC3) proteins.