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FAM20A is a golgi-localized Type II transmembrane protein.

ABSTRACT: Family with sequence similarity 20, member A (FAM20A) is a pseudo-kinase in the secretory pathway and is essential for enamel formation in humans. Here we examine if FAM20A is a membrane-associated protein. We show that the full-length FAM20A can be purified from HEK293 cells transfected with a FAM20A-expresing construct. Further, it is only found in the membrane fraction, but not in the soluble fraction, of cell lysate. Consistently, it is not secreted out of the expressing cells. Moreover, it is co-localized with GM130, a cis-Golgi network marker, and membrane topology analysis indicates that it has its C-terminus oriented towards the lumen of the organelle. Our results support that FAM20A is a Type II transmembrane protein within the secretory compartments.

SUBMITTER: Siddiqui MF

PROVIDER: S-EPMC10948845 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature

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FAM20A is a golgi-localized Type II transmembrane protein.

Siddiqui Mohammad Faizan MF Li Jiahe J Wang Suzhen S Zhang Hua H Qin Chunlin C Lu Yongbo Y

Scientific reports 20240318 1

Family with sequence similarity 20, member A (FAM20A) is a pseudo-kinase in the secretory pathway and is essential for enamel formation in humans. Here we examine if FAM20A is a membrane-associated protein. We show that the full-length FAM20A can be purified from HEK293 cells transfected with a FAM20A-expresing construct. Further, it is only found in the membrane fraction, but not in the soluble fraction, of cell lysate. Consistently, it is not secreted out of the expressing cells. Moreover, it ...[more]

PMID: 38499693

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