TY - JOUR

T1 - Brain-specific glycosylation of protein tyrosine phosphatase receptor type Z (PTPRZ) marks a demyelination-associated astrocyte subtype

AU - Takahashi, Kazuto

AU - Kanekiyo, Kenji

AU - Sakuda, Kanoko

AU - Muto, Yui

AU - Iguchi, Masahiro

AU - Matsuda, Nozomu

AU - Hashimoto, Yuko

AU - Kanai, Kazuaki

AU - Ogawa, Haruko

AU - Hirase, Hajime

AU - Kakita, Akiyoshi

AU - Bizen, Norihisa

AU - Takebayashi, Hirohide

AU - Kawaguchi, Yasushi

AU - Uzuki, Miwa

AU - Kitazume, Shinobu

N1 - Publisher Copyright: © 2023 International Society for Neurochemistry.

PY - 2023

Y1 - 2023

N2 - Astrocytes are the most abundant glial cell type in the brain, where they participate in various homeostatic functions. Transcriptomically, diverse astrocyte subpopulations play distinct roles during development and disease progression. However, the biochemical identification of astrocyte subtypes, especially by membrane surface protein glycosylation, remains poorly investigated. Protein tyrosine phosphatase receptor type zeta (PTPRZ) is a highly expressed membrane protein in CNS glia cells that can be modified with diverse glycosylation, including the unique HNK-1 capped O-mannosyl (O-Man) core M2 glycan mediated by brain-specific branching enzyme GnT-IX. Although PTPRZ modified with HNK-1 capped O-Man glycans (HNK-1-O-Man+ PTPRZ) is increased in reactive astrocytes of demyelination model mice, whether such astrocytes emerge in a broad range of disease-associated conditions or are limited to conditions associated with demyelination remains unclear. Here, we show that HNK-1-O-Man+ PTPRZ localizes in hypertrophic astrocytes of damaged brain areas in patients with multiple sclerosis. Furthermore, we show that astrocytes expressing HNK-1-O-Man+ PTPRZ are present in two demyelination mouse models (cuprizone-fed mice and a vanishing white matter disease model), while traumatic brain injury does not induce glycosylation. Administration of cuprizone to Aldh1l1-eGFP and Olig2KICreER/+;Rosa26eGFP mice revealed that cells expressing HNK-1-O-Man+ PTPRZ are derived from cells in the astrocyte lineage. Notably, GnT-IX but not PTPRZ mRNA was up-regulated in astrocytes isolated from the corpus callosum of cuprizone model mice. These results suggest that the unique PTPRZ glycosylation plays a key role in the patterning of demyelination-associated astrocytes. (Figure presented.)

AB - Astrocytes are the most abundant glial cell type in the brain, where they participate in various homeostatic functions. Transcriptomically, diverse astrocyte subpopulations play distinct roles during development and disease progression. However, the biochemical identification of astrocyte subtypes, especially by membrane surface protein glycosylation, remains poorly investigated. Protein tyrosine phosphatase receptor type zeta (PTPRZ) is a highly expressed membrane protein in CNS glia cells that can be modified with diverse glycosylation, including the unique HNK-1 capped O-mannosyl (O-Man) core M2 glycan mediated by brain-specific branching enzyme GnT-IX. Although PTPRZ modified with HNK-1 capped O-Man glycans (HNK-1-O-Man+ PTPRZ) is increased in reactive astrocytes of demyelination model mice, whether such astrocytes emerge in a broad range of disease-associated conditions or are limited to conditions associated with demyelination remains unclear. Here, we show that HNK-1-O-Man+ PTPRZ localizes in hypertrophic astrocytes of damaged brain areas in patients with multiple sclerosis. Furthermore, we show that astrocytes expressing HNK-1-O-Man+ PTPRZ are present in two demyelination mouse models (cuprizone-fed mice and a vanishing white matter disease model), while traumatic brain injury does not induce glycosylation. Administration of cuprizone to Aldh1l1-eGFP and Olig2KICreER/+;Rosa26eGFP mice revealed that cells expressing HNK-1-O-Man+ PTPRZ are derived from cells in the astrocyte lineage. Notably, GnT-IX but not PTPRZ mRNA was up-regulated in astrocytes isolated from the corpus callosum of cuprizone model mice. These results suggest that the unique PTPRZ glycosylation plays a key role in the patterning of demyelination-associated astrocytes. (Figure presented.)

KW - Astrocytes

KW - Demyelination

KW - GnT-IX

KW - HNK-1-O-Man

KW - multiple

KW - PTPRZ

KW - sclerosis

U2 - 10.1111/jnc.15820

DO - 10.1111/jnc.15820

M3 - Journal article

C2 - 37005741

AN - SCOPUS:85153175747

VL - 166

JO - Journal of Neurochemistry

JF - Journal of Neurochemistry

SN - 0022-3042

IS - 3

ER -