OTOR Human

Otoraplin is predominantly expressed in the cochlea of the inner ear and to a lesser extent in the fetal brain and some cartilage tissues . It plays a crucial role in early chondrogenesis of the otic capsule, which is essential for normal inner ear development and auditory function . Additionally, Otoraplin is highly homologous to MIA/cartilage-derived retinoic acid-sensitive protein (CD-RAP), a cartilage-specific protein also expressed in malignant melanoma cells .

The mature human Otoraplin consists of 111 amino acids and contains one SH3 domain (amino acids 46-107). It also has a tyrosine residue at position 50 that is reportedly sulfated . The recombinant human Otoraplin (rhOTOR) produced in CHO cells is a single non-glycosylated polypeptide chain with a molecular mass of approximately 14-15 kDa as analyzed by reducing SDS-PAGE .

Recombinant human Otoraplin is typically produced in Escherichia coli (E. coli) or Chinese Hamster Ovary (CHO) cells. The protein is purified to a high degree, often exceeding 95% purity as analyzed by SDS-PAGE . The endotoxin level is kept below 0.2 EU/μg, determined by the Limulus Amebocyte Lysate (LAL) method .

Otoraplin is used in various research applications, particularly those related to inner ear development, auditory function, and cartilage formation. Its role in early chondrogenesis makes it a valuable tool for studying the molecular mechanisms underlying these processes .

The lyophilized preparation of recombinant human Otoraplin is stable at 2-8°C but should be kept at -20°C for long-term storage. Upon reconstitution, the preparation is most stable at -20°C to -80°C and can be stored for one week at 2-8°C. For maximal stability, it is recommended to apportion the reconstituted preparation into working aliquots and store at -20°C to -80°C, avoiding repeated freeze/thaw cycles .