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A study of the expression and cellular function of the human FAM111B gene

POIKTMP, a multi-systemic fibrosing disease, results from mutations in the human FAM111B gene. Studies have also suggested high expression of this gene in cancers. Despite rising interest in the pathological effects of FAM111B mutations and overexpression of FAM111B, knowledge of the physiological r...

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Main Author: Rhoda, Cenza
Other Authors: Arowolo, Afolake
Format: Thesis
Language:English
Published: Department of Medicine 2022
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access_status_str Open Access
author Rhoda, Cenza
author2 Arowolo, Afolake
author_browse Arowolo, Afolake
Rhoda, Cenza
author_facet Arowolo, Afolake
Rhoda, Cenza
author_sort Rhoda, Cenza
collection Thesis
description POIKTMP, a multi-systemic fibrosing disease, results from mutations in the human FAM111B gene. Studies have also suggested high expression of this gene in cancers. Despite rising interest in the pathological effects of FAM111B mutations and overexpression of FAM111B, knowledge of the physiological role of this gene remains limited. Therefore, this study sought out to provide insights into the cellular function of FAM111B and to investigate the pathological effect of the FAM111B Y621D mutation. First, bioinformatics studies coupled with quantitative PCR and Western blots analysis were employed to assess FAM111B gene and protein expression in cancerous and non-cancerous cell lines. Subsequently, FAM111B gene expression was downregulated and upregulated in the human fibrosarcoma (HT1080) cell line by RNA-interference mediated gene silencing and recombinant gene expression technologies. The effect of these FAM111B dysregulations was studied using cellbased functional assays: proliferation, apoptosis, migration, and invasion assays. Furthermore, the functional pathways and interacting proteins of the FAM111B protein was determined using mass spectroscopy proteomics. Finally, preliminary studies in a POIKTMP patient-derived fibroblasts were attempted to recapitulate the results obtained using the HT1080 cell line. The results from this study indicated that FAM111B gene and protein overexpression occurs in cancer cells. Second, the depletion of FAM111B suggests a decelerated rate of cell proliferation and migration (14%), and increased apoptosis (1.4-fold). Conversely, overexpression of FAM111B resulted in a marked reduction in apoptosis (3-fold) and increased cell migration by 27 %, howbeit, no evidence of increased proliferation. Furthermore, Y621D FAM111B mutant cells showed reduced expression of FAM111B, decreased apoptosis (1.1-fold), cellular invasion (24%), and indicates an increase in cell proliferation and migration (18 %). The proteomics data suggested wild-type FAM111B interacts with HSP7C, a molecular chaperone, which alongside BAG3 and BCL2 to minimise apoptosis. Similarly, Y621D's interaction with G3V3W4, a component of the 20S proteasome complex involved in the proteolytic degradation of damaged proteins, may suggest the rapid clearance of this mutant protein.
format Thesis
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institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:33:04.194Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2022
publishDateRange 2022
publishDateSort 2022
publisher Department of Medicine
publisherStr Department of Medicine
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source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/36135 A study of the expression and cellular function of the human FAM111B gene Rhoda, Cenza Arowolo, Afolake Medicine POIKTMP, a multi-systemic fibrosing disease, results from mutations in the human FAM111B gene. Studies have also suggested high expression of this gene in cancers. Despite rising interest in the pathological effects of FAM111B mutations and overexpression of FAM111B, knowledge of the physiological role of this gene remains limited. Therefore, this study sought out to provide insights into the cellular function of FAM111B and to investigate the pathological effect of the FAM111B Y621D mutation. First, bioinformatics studies coupled with quantitative PCR and Western blots analysis were employed to assess FAM111B gene and protein expression in cancerous and non-cancerous cell lines. Subsequently, FAM111B gene expression was downregulated and upregulated in the human fibrosarcoma (HT1080) cell line by RNA-interference mediated gene silencing and recombinant gene expression technologies. The effect of these FAM111B dysregulations was studied using cellbased functional assays: proliferation, apoptosis, migration, and invasion assays. Furthermore, the functional pathways and interacting proteins of the FAM111B protein was determined using mass spectroscopy proteomics. Finally, preliminary studies in a POIKTMP patient-derived fibroblasts were attempted to recapitulate the results obtained using the HT1080 cell line. The results from this study indicated that FAM111B gene and protein overexpression occurs in cancer cells. Second, the depletion of FAM111B suggests a decelerated rate of cell proliferation and migration (14%), and increased apoptosis (1.4-fold). Conversely, overexpression of FAM111B resulted in a marked reduction in apoptosis (3-fold) and increased cell migration by 27 %, howbeit, no evidence of increased proliferation. Furthermore, Y621D FAM111B mutant cells showed reduced expression of FAM111B, decreased apoptosis (1.1-fold), cellular invasion (24%), and indicates an increase in cell proliferation and migration (18 %). The proteomics data suggested wild-type FAM111B interacts with HSP7C, a molecular chaperone, which alongside BAG3 and BCL2 to minimise apoptosis. Similarly, Y621D's interaction with G3V3W4, a component of the 20S proteasome complex involved in the proteolytic degradation of damaged proteins, may suggest the rapid clearance of this mutant protein. 2022-03-16T06:38:35Z 2022-03-16T06:38:35Z 2021 2022-03-16T00:53:38Z Master Thesis Masters MSc http://hdl.handle.net/11427/36135 eng application/pdf Department of Medicine Faculty of Health Sciences
spellingShingle Medicine
Rhoda, Cenza
A study of the expression and cellular function of the human FAM111B gene
thesis_degree_str Master's
title A study of the expression and cellular function of the human FAM111B gene
title_full A study of the expression and cellular function of the human FAM111B gene
title_fullStr A study of the expression and cellular function of the human FAM111B gene
title_full_unstemmed A study of the expression and cellular function of the human FAM111B gene
title_short A study of the expression and cellular function of the human FAM111B gene
title_sort study of the expression and cellular function of the human fam111b gene
topic Medicine
url http://hdl.handle.net/11427/36135
work_keys_str_mv AT rhodacenza astudyoftheexpressionandcellularfunctionofthehumanfam111bgene
AT rhodacenza studyoftheexpressionandcellularfunctionofthehumanfam111bgene