Acts as one of several non-catalytic accessory components of the cytoplasmic dynein 1 complex that are thought to be involved in linking dynein to cargos and to adapter proteins that regulate dynein function. Cytoplasmic dynein 1 acts as a motor for the intracellular retrograde motility of vesicles and organelles along microtubules. The intermediate chains mediate the binding of dynein to dynactin via its 150 kDa component (p150-glued) DCTN1. May play a role in mediating the interaction of cytoplasmic dynein with membranous organelles and kinetochores. Homodimer (By similarity). The cytoplasmic dynein 1 complex consists of two catalytic heavy chains (HCs) and a number of non-catalytic subunits presented by intermediate chains (ICs), light intermediate chains (LICs) and light chains (LCs); the composition seems to vary in respect to the IC, LIC and LC composition. The heavy chain homodimer serves as a scaffold for the probable homodimeric assembly of the respective non-catalytic subunits. The ICs and LICs bind directly to the HC dimer and the LCs assemble on the IC dimer. Isoform 1, isoform 2 and isoform 3 interact with DYNC1H1. Isoform 1, isoform 2 and isoform 3 interact with DYNLT3. Isoform 1, isoform 2 and isoform 3 interact with DYNLT1. Interacts with DCTN1. High levels seen in the brain and testis, while a lower level expression is seen in the liver, spleen, kidney, lung, skeletal muscle and heart. Belongs to the dynein intermediate chain family.