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Calcium signalling in mammalian cell lines expressing wild type and mutant human ?1-Antitrypsin.

ABSTRACT: A possible role for calcium signalling in the autosomal dominant form of dementia, familial encephalopathy with neuroserpin inclusion bodies (FENIB), has been proposed, which may point towards a mechanism by which cells could sense and respond to the accumulation of mutant serpin polymers in the endoplasmic reticulum (ER). We therefore explored possible defects in Ca2+-signalling, which may contribute to the pathology associated with another serpinopathy, ?1-antitrypsin (AAT) deficiency. Using CHO K1 cell lines stably expressing a wild type human AAT (MAAT) and a disease-causing polymer-forming variant (ZAAT) and the truncated variant (NHK AAT), we measured basal intracellular free Ca2+, its responses to thapsigargin (TG), an ER Ca2+-ATPase blocker, and store-operated Ca2+-entry (SOCE). Our fura2 based Ca2+ measurements detected no differences between these 3 parameters in cell lines expressing MAAT and cell lines expressing ZAAT and NHK AAT mutants. Thus, in our cell-based models of ?1-antitrypsin (AAT) deficiency, unlike the case for FENIB, we were unable to detect defects in calcium signalling.

SUBMITTER: Malintan NT

PROVIDER: S-EPMC6872872 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Calcium signalling in mammalian cell lines expressing wild type and mutant human α1-Antitrypsin.

Malintan Nancy T NT Buckingham Steven D SD Lomas David A DA Sattelle David B DB

Scientific reports 20191121 1

A possible role for calcium signalling in the autosomal dominant form of dementia, familial encephalopathy with neuroserpin inclusion bodies (FENIB), has been proposed, which may point towards a mechanism by which cells could sense and respond to the accumulation of mutant serpin polymers in the endoplasmic reticulum (ER). We therefore explored possible defects in Ca<sup>2+</sup>-signalling, which may contribute to the pathology associated with another serpinopathy, α<sub>1</sub>-antitrypsin (AA ...[more]

PMID: 31754242

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Calcium signalling in mammalian cell lines expressing wild type and mutant human ?1-Antitrypsin.

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Calcium signalling in mammalian cell lines expressing wild type and mutant human α1-Antitrypsin.

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