mu-Crystallins

**Definition:** A subclass of crystallins expressed highly in lens of diurnal Australian MARSUPIALS and in neural tissue, muscle, and kidney in humans. It is not a structural protein accounting for the transparency of the human lens unlike other crystallins but instead plays a role in thyroid hormone bioavailability. It is also a cerebral ketimine reductase which reduces cyclic imines (e.g., DELTA(1)-PIPERIDINE-2-CARBOXYLIC ACID; CYSTATHIONINE KETIMINE and LANTHIONINE KETIMINE) in mammalian brain. Mutations in mu-crystallins are associated with an autosomal dominant NONSYNDROMIC DEAFNESS.

**Tree numbers:** - D08.811.682.662.436 - D12.776.306.366.888

**Synonyms:** - Crystallin mu - Ketimine Reductase mu-Crystallin - CRYM Protein - THBP Protein - NADP-Regulated Thyroid Hormone Binding Protein