Publications by authors named "Natasha A Pereira"

Therapeutic monoclonal antibodies are the fastest growing class of biological therapeutics for the treatment of various cancers and inflammatory disorders. In cancer immunotherapy, some IgG1 antibodies rely on the Fc-mediated immune effector function, antibody-dependent cellular cytotoxicity (ADCC), as the major mode of action to deplete tumor cells. It is well-known that this effector function is modulated by the N-linked glycosylation in the Fc region of the antibody.

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Translocation of a nascent protein from the cytosol into the ER mediated by its signal peptide is a critical step in protein secretion. The aim of this work was to develop a platform technology to optimize the signal peptides for high level production of therapeutic antibodies in CHO cells. A database of signal peptides from a large number of human immunoglobulin (Ig) heavy chain (HC) and kappa light chain (LC) was generated.

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The innate immune system senses cytosolic dsDNA and bacterial cyclic dinucleotides and initiates signaling via the adaptor STING to induce type 1 interferon (IFN) response. We demonstrate here that BTK-deficient cells have impaired IFN-β production and TBK1/IRF3 activation when stimulated with agonists or infected with pathogens that activate STING signaling. BTK interacts with STING and DDX41 helicase.

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The downstream of kinase (DOK) family of adaptors is generally involved in the negative regulation of signaling pathways. DOK1, 2, and 3 were shown to attenuate TLR4 signaling by inhibiting Ras-ERK activation. In this study, we elucidated a novel role for DOK3 in IFN-β production.

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GOLPH3 is a highly conserved protein found across the eukaryotic lineage. The yeast homolog, Vps74p, interacts with and maintains the Golgi localization of several mannosyltransferases, which is subsequently critical for N- and O-glycosylation in yeast. Through the use of a T7 phage display, we discovered a novel interaction between GOLPH3 and a mammalian glycosyltransferase, POMGnT1, which is involved in the O-mannosylation of α-dystroglycan.

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The GDP-fucose transporter SLC35C1 critically regulates the fucosylation of glycans. Elucidation of its structure-function relationships remains a challenge due to the lack of an appropriate mutant cell line. Here we report a novel Chinese hamster ovary (CHO) mutant, CHO-gmt5, generated by the zinc-finger nuclease technology, in which the Slc35c1 gene was knocked out from a previously reported CHO mutant that has a dysfunctional CMP-sialic acid transporter (CST) gene (Slc35a1).

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Many designated substrates and inhibitors have been widely used to investigate the roles of caspases in apoptotic death during mammalian cell culture. However, the specificities of these substrates and inhibitors have not been systematically evaluated. As a result, conclusions on the roles of specific caspases in apoptotic cells have been published inaccurately.

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The Bcl-2 family of proteins interacts at the mitochondria to regulate apoptosis. However, the anti-apoptotic Bcl-2 and Bcl-X(L) are not completely localized to the mitochondria. In an attempt to generate Bcl-2 and Bcl-X(L) chimeras that are constitutively localized to the mitochondria, we substituted their C-terminal transmembrane tail or both the C-terminal transmembrane tail and the adjacent loop with the equivalent regions from Bak or Bax mutant (BaxS184V) as these regions determine the mitochondrial localization of Bak and Bax.

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