PA28 alpha beta Reduces Size and Increases Hydrophilicity of 20S Immunoproteasome Peptide Products

Mary Raule, Fulvia Cerruti, Nadia Benaroudj, Rebekka Migotti, Julia Kikuchi, Angela Bachi, Ami Navon, Gunnar Dittmar, Paolo Cascio

نتاج البحث: نشر في مجلةمقالةمراجعة النظراء

ملخص

The specific roles that immunoproteasome variants play in MHC class I antigen presentation are unknown at present. To investigate the biochemical properties of different immunoproteasome forms and unveil the molecular mechanisms of PA28 activity, we performed in vitro degradation of full-length proteins by 20S, 26S, and PA28 alpha beta-20S immunoproteasomes and analyzed the spectrum of peptides released. Notably, PA28 alpha beta-20S immunoproteasomes hydrolyze proteins at the same low rates as 20S alone, which is in line with PA28, neither stimulating nor preventing entry of unfolded polypeptides into the core particle. Most importantly, binding of PA28 alpha beta to 20S greatly reduces the size of proteasomal products and favors the release of specific, more hydrophilic, longer peptides. Hence, PA28 alpha beta may either allosterically modify proteasome active sites or act as a selective "smart" sieve that controls the efflux of products from the 20S proteolytic chamber.
اللغة الأصليةالإنجليزيّة
الصفحات (من إلى)470-480
عدد الصفحات11
دوريةChemistry & Biology
مستوى الصوت21
رقم الإصدار4
المعرِّفات الرقمية للأشياء
حالة النشرنُشِر - 24 أبريل 2014

All Science Journal Classification (ASJC) codes

  • !!Biochemistry
  • !!Molecular Medicine
  • !!Molecular Biology
  • !!Pharmacology
  • !!Drug Discovery
  • !!Clinical Biochemistry

بصمة

أدرس بدقة موضوعات البحث “PA28 alpha beta Reduces Size and Increases Hydrophilicity of 20S Immunoproteasome Peptide Products'. فهما يشكلان معًا بصمة فريدة.

قم بذكر هذا