title: Developmental Stage-dependent Regulation of Prolyl 3-Hydroxylation in Tendon Type I Collagen.
abstract: 3-Hydroxyproline (3-Hyp), which is unique to collagen, is a fairly rare post-translational modification. Recent studies have suggested a function of prolyl 3-hydroxylation in fibril assembly and its relationships with certain disorders, including recessive osteogenesis imperfecta and high myopia. However, no direct evidence for the physiological and pathological roles of 3-Hyp has been presented. In this study, we first estimated the overall alterations in prolyl hydroxylation in collagens purified from skin, bone, and tail tendon of 0.5-18-month-old rats by LC-MS analysis with stable isotope-labeled collagen, which was recently developed as an internal standard for highly accurate collagen analyses. 3-Hyp was found to significantly increase in tendon collagen until 3 months after birth and then remain constant, whereas increased prolyl 3-hydroxylation was not observed in skin and bone collagen. Site-specific analysis further revealed that 3-Hyp was increased in tendon type I collagen in a specific sequence region, including a previously known modification site at Pro(707) and newly identified sites at Pro(716) and Pro(719), at the early ages. The site-specific alterations in prolyl 3-hydroxylation with aging were also observed in bovine Achilles tendon. We postulate that significant increases in 3-Hyp at the consecutive modification sites are correlated with tissue development in tendon. The present findings suggest that prolyl 3-hydroxylation incrementally regulates collagen fibril diameter in tendon.
authors.affiliation: From the Nippi Research Institute of Biomatrix, Toride, Ibaraki 302-0017, Japan y-taga@nippi-inc.co.jp.
authors.forename: Yuki
authors.identifier: http://orcid.org/0000-0001-9100-758X
authors.initials: Y
authors.lastname: Taga
authors.affiliation: From the Nippi Research Institute of Biomatrix, Toride, Ibaraki 302-0017, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Kusubata
authors.affiliation: From the Nippi Research Institute of Biomatrix, Toride, Ibaraki 302-0017, Japan.
authors.forename: Kiyoko
authors.initials: K
authors.lastname: Ogawa-Goto
authors.affiliation: From the Nippi Research Institute of Biomatrix, Toride, Ibaraki 302-0017, Japan.
authors.forename: Shunji
authors.initials: S
authors.lastname: Hattori
mesh_terms: D000375:Aging / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001842:Bone and Bones / Q000378:metabolism; D002417:Cattle; D024042:Collagen Type I / Q000737:chemistry / Q000378:metabolism*; D006900:Hydroxylation; D006909:Hydroxyproline / Q000378:metabolism*; D008297:Male; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000378:metabolism; D013710:Tendons / Q000378:metabolism*
chemical_list: D024042:Collagen Type I; D010455:Peptides; C026215:3-hydroxyproline; D006909:Hydroxyproline
keywords: 3-hydroxyproline; collagen; development; mass spectrometry (MS); post-translational modification (PTM); tendon