Titin

Just found out the longest word in the world - the chemical name for Titin. Titin is the largest protein that has been discovered by the scientists so far. It's full chemical name has 189819 letters!! However, it is not included in the dictionary. (As you know, chemical names are usually not found in the dictionary) Titin is a protein that in humans that is encoded by the TTN gene. It is important in the contraction of striated muscle tissues. Titin connects the Z line to the M line in the sarcomere. The protein limits the range of motion of the sarcomere in tension, thus contributing to the passive stiffness of muscle. Variations in the sequence of titin between different types of muscle (e.g. cardiac or skeletal) has been correlated with differences in the mechanical properties of the muscles. It is also the largest known single polypeptide. The gene for titin also contains the largest number of introns (363) discovered in any single gene.
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