Dataset Information

Ascorbate inducible N259 glycans on prolyl 4-hydroxylase subunit ?1 promote hydroxylation and secretion of type I collagen.

ABSTRACT: Ascorbic acid (vitamin C, VC) increases the secretion of mature collagen by promoting the activity of prolyl 4-hydroxylase subunit ? 1 (P4HA1). To explore the mechanism involved, we investigated the role of N-linked glycosylation, which can regulate enzyme activity. P4HA1 has two glycosylation sites, Asn (N) 113 and N259. Our studies show that glycosylation of N259, but not N113, by STT3B and magnesium transporter 1 (MAGT1) is augmented by VC. N259 glycosylation on P4HA1 correlates with enhanced pepsin-resistant collagen 1?2 secretion. Downregulation of Stt3b and Magt1 reduces N259 glycans on P4HA1. In collagen 1?2 purified from Stt3b-silenced fibroblasts, decreased hydroxylation is found at five specific proline residues, while significantly increased hydroxylation is noted at two proline residues. Similarly, in collagen 1?1, reduced proline hydroxylation is detected at eight sites and increased proline hydroxylation is found at four sites. These results suggest that N-linked glycosylation of P4HA1 can direct hydroxylation at specific proline residues and affect collagen maturation.

SUBMITTER: Shi R

PROVIDER: S-EPMC6698205 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Ascorbate inducible N259 glycans on prolyl 4-hydroxylase subunit α1 promote hydroxylation and secretion of type I collagen.

Shi Run R Hu Weimin W Zhang Yan Y Gao Shanshan S Smith Andrew H AH Ye Jun J Cai Lili L Graham Linda M LM Li Chaoyang C

Cellular and molecular life sciences : CMLS 20190327 17

Ascorbic acid (vitamin C, VC) increases the secretion of mature collagen by promoting the activity of prolyl 4-hydroxylase subunit α 1 (P4HA1). To explore the mechanism involved, we investigated the role of N-linked glycosylation, which can regulate enzyme activity. P4HA1 has two glycosylation sites, Asn (N) 113 and N259. Our studies show that glycosylation of N259, but not N113, by STT3B and magnesium transporter 1 (MAGT1) is augmented by VC. N259 glycosylation on P4HA1 correlates with enhanced ...[more]

PMID: 30919021

Similar Datasets

Project description:Increased collagen deposition provides physical and biochemical signals to support tumor growth and invasion during breast cancer development. Therefore, inhibition of collagen synthesis and deposition has been considered a strategy to suppress breast cancer progression. Collagen prolyl-4-hydroxylase ? subunit 2 (P4HA2), an enzyme hydroxylating proline residues in -X-Pro-Gly- sequences, is a potential therapeutic target for the disorders associated with increased collagen deposition. However, expression and function of P4HA2 in breast cancer progression are not well investigated.Gene co-expression analysis was performed in the published microarray datasets to identify potential regulators of collagen I, III, and IV in human breast cancer tissue. Expression of P4HA2 was silenced by shRNAs, and its activity was inhibited by 1, 4-DPCA, a prolyl-4-hydroxylase inhibitor. Three-dimensional culture assay was used to analyze roles of P4HA2 in regulating malignant phenotypes of breast cancer cells. Reduced deposition of collagen I and IV was detected by Western blotting and immunofluorescence. Control and P4HA2-silenced breast cancer cells were injected into fat pad and tail vein of SCID mice to examine effect of P4HA2 on tumor growth and lung metastasis.Using gene co-expression analysis, we showed that P4HA2 was associated with expression of Col1A1, Col3A1, and Col4A1 during breast cancer development and progression. P4HA2 mRNA levels were significantly upregulated in breast cancer compared to normal mammary tissue. Increased mRNA levels of P4HA2 correlated with poor clinical outcome in breast cancer patients, which is independent of estrogen receptor status. Silencing P4HA2 expression or treatment with the P4HA inhibitor significantly inhibited cell proliferation and suppressed aggressive phenotypes of breast cancer cells in 3D culture, accompanied by reduced deposition of collagen I and IV. We also found that knockdown of P4HA2 inhibited mammary tumor growth and metastasis to lungs in xenograft models.These results suggest the critical role of P4HA2 in breast cancer progression and identify P4HA2 as a potential therapeutic target and biomarker for breast cancer progression.

Project description:Mutations in the genes encoding cartilage associated protein (CRTAP) and prolyl 3-hydroxylase 1 (P3H1 encoded by LEPRE1) were the first identified causes of recessive Osteogenesis Imperfecta (OI). These proteins, together with cyclophilin B (encoded by PPIB), form a complex that 3-hydroxylates a single proline residue on the α1(I) chain (Pro986) and has cis/trans isomerase (PPIase) activity essential for proper collagen folding. Recent data suggest that prolyl 3-hydroxylation of Pro986 is not required for the structural stability of collagen; however, the absence of this post-translational modification may disrupt protein-protein interactions integral for proper collagen folding and lead to collagen over-modification. P3H1 and CRTAP stabilize each other and absence of one results in degradation of the other. Hence, hypomorphic or loss of function mutations of either gene cause loss of the whole complex and its associated functions. The relative contribution of losing this complex's 3-hydroxylation versus PPIase and collagen chaperone activities to the phenotype of recessive OI is unknown. To distinguish between these functions, we generated knock-in mice carrying a single amino acid substitution in the catalytic site of P3h1 (Lepre1(H662A) ). This substitution abolished P3h1 activity but retained ability to form a complex with Crtap and thus the collagen chaperone function. Knock-in mice showed absence of prolyl 3-hydroxylation at Pro986 of the α1(I) and α1(II) collagen chains but no significant over-modification at other collagen residues. They were normal in appearance, had no growth defects and normal cartilage growth plate histology but showed decreased trabecular bone mass. This new mouse model recapitulates elements of the bone phenotype of OI but not the cartilage and growth phenotypes caused by loss of the prolyl 3-hydroxylation complex. Our observations suggest differential tissue consequences due to selective inactivation of P3H1 hydroxylase activity versus complete ablation of the prolyl 3-hydroxylation complex.

Dataset Information

Ascorbate inducible N259 glycans on prolyl 4-hydroxylase subunit ?1 promote hydroxylation and secretion of type I collagen.

Publications

Ascorbate inducible N259 glycans on prolyl 4-hydroxylase subunit α1 promote hydroxylation and secretion of type I collagen.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets