cuticulosome
{{Short description|Anatomical structure in birds}}
The cuticulosome is a spherical, iron-rich structure located in the cuticular plate of auditory and vestibular hair cells in birds.{{Cite journal|last1=Lauwers|first1=Mattias|last2=Pichler|first2=Paul|last3=Edelman|first3=Nathaniel Bernard|last4=Resch|first4=Guenter Paul|last5=Ushakova|first5=Lyubov|last6=Salzer|first6=Marion Claudia|last7=Heyers|first7=Dominik|last8=Saunders|first8=Martin|last9=Shaw|first9=Jeremy|date=May 2013|title=An Iron-Rich Organelle in the Cuticular Plate of Avian Hair Cells|journal=Current Biology|volume=23|issue=10|pages=924–929|doi=10.1016/j.cub.2013.04.025|pmid=23623555|issn=0960-9822|doi-access=free}}{{Cite journal|last1=Nimpf|first1=Simon|authorlink2=Erich Pascal Malkemper|last2=Malkemper|first2=Erich Pascal|last3=Lauwers|first3=Mattias|last4=Ushakova|first4=Lyubov|last5=Nordmann|first5=Gregory|last6=Wenninger-Weinzierl|first6=Andrea|last7=Burkard|first7=Thomas R|last8=Jacob|first8=Sonja|last9=Heuser|first9=Thomas|date=2017-11-15|title=Subcellular analysis of pigeon hair cells implicates vesicular trafficking in cuticulosome formation and maintenance|journal=eLife|language=en|volume=6|doi=10.7554/elife.29959|issn=2050-084X|pmc=5699870|pmid=29140244 |doi-access=free }} Cuticulosomes are 300-600 nm in diameter and are composed of ferritin-like granules that in some cases are structured in paracrystalline arrays. Due to its specific location in sensory hair cells of the inner ear and its iron-rich composition it was proposed to be involved in the magnetic sense of birds. However, physical simulations and calculations showed that it lacks sufficient magnetic susceptibility to act as a torque based magnetoreceptor.{{Cite journal|last1=Jandacka|first1=Petr|last2=Burda|first2=Hynek|last3=Pistora|first3=Jaromir|date=2015-01-06|title=Magnetically induced behaviour of ferritin corpuscles in avian ears: can cuticulosomes function as magnetosomes?|journal=Journal of the Royal Society Interface|language=en|volume=12|issue=102|pages=20141087|doi=10.1098/rsif.2014.1087|issn=1742-5689|pmc=4277103|pmid=25551148}} An alternative hypothesis suggests that the cuticulosome might work as an intracellular electromagnetic oscillator to detect magnetic fields.