Metallotiyoninlerin Histofizyolojik Önemi

Öz

Metallotiyoninler (MT) düşük molekül ağırlıklı (6000-7000 Da), 20 sistein molekülü içeren 61 amino asitli hücre içi proteinlerdir. MT proteini çinko, bakır, kadmiyum, civa, kurşun gibi metalleri bağlama yeteneğine sahiptir. Bu proteinler akciğer, böbrek, pankreas ve karaciğerin paranşimal hücrelerinde, barsakların epitellerinde, sertoli hücrelerinde, timulin içeren timus epitel hücrelerinde, germinatif hücrelerde, miyoepitel hücrelerinde normal olarak bol miktarda bulunmaktadır. MT’lerin önemi; ağır metallerin ve iz elementlerin homeostazisinde, detoksifikasyonunda ve taşınmasında görev almasıdır. Ayrıca, MT’ler hemhücrelerin gelişmesinde hem de apoptozis ve nekrozis gibi hücre ölümleriyle de ilşkileri bulunmaktadır.

Anahtar Kelimeler

• Metallotiyoninler, ağır metaller, iz elementler

Kaynakça

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