Expression and Functional Characteristics of Calpain 3 Isoforms Generated through Tissue-Specific Transcriptional and Posttranscriptional Events

ABSTRACT Calpain 3 is a nonlysosomal cysteine protease whose biological functions remain unknown. We previously demonstrated that this protease is altered in limb girdle muscular dystrophy type 2A patients. Preliminary observations suggested that its gene is subjected to alternative splicing. In this paper, we characterize transcriptional and posttranscriptional events leading to alterations involving the NS, IS1, and IS2 regions and/or the calcium binding domains of the mouse calpain 3 gene (capn3). These events can be divided into three groups: (i) splicing of exons that preserve the translation frame, (ii) inclusion of two distinct intronic sequences between exons 16 and 17 that disrupt the frame and would lead, if translated, to a truncated protein lacking domain IV, and (iii) use of an alternative first exon specific to lens tissue. In addition, expression of these isoforms seems to be regulated. Investigation of the proteolytic activities and titin binding abilities of the translation products of some of these isoforms clearly indicated that removal of these different protein segments affects differentially the biochemical properties examined. In particular, removal of exon 6 impaired the autolytic but not fodrinolytic activity and loss of exon 16 led to an increased titin binding and a loss of fodrinolytic activity. These results are likely to impact our understanding of the pathophysiology of calpainopathies and the development of therapeutic strategies.

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Courtship and Visual Defects of cacophony Mutants Reveal Functional Complexity of a Calcium-Channel α1 Subunit in Drosophila

Genetics ◽

10.1093/genetics/149.3.1407 ◽

1998 ◽

Vol 149 (3) ◽

pp. 1407-1426 ◽

Cited By ~ 4

Author(s):

Lee A Smith ◽

Alexandre A Peixoto ◽

Elena M Kramer ◽

Adriana Villella ◽

Jeffrey C Hall

Keyword(s):

Alternative Splicing ◽

Calcium Channels ◽

Calcium Channel ◽

Stop Codon ◽

Biological Functions ◽

Visual Defects ◽

Transcript Diversity ◽

Functional Complexity ◽

Α1 Subunit ◽

Subtle Abnormality

Abstract We show by molecular analysis of behavioral and physiological mutants that the Drosophila Dmca1A calcium-channel α1 subunit is encoded by the cacophony (cac) gene and that nightblind-A and lethal(1)L13 mutations are allelic to cac with respect to an expanded array of behavioral and physiological phenotypes associated with this gene. The cacS mutant, which exhibits defects in the patterning of courtship lovesong and a newly revealed but subtle abnormality in visual physiology, is mutated such that a highly conserved phenylalanine (in one of the quasi-homologous intrapolypeptide regions called IIIS6) is replaced by isoleucine. The cacH18 mutant exhibits defects in visual physiology (including complete unresponsiveness to light in certain genetic combinations) and visually mediated behaviors; this mutant (originally nbAH18) has a stop codon in an alternative exon (within the cac ORF), which is differentially expressed in the eye. Analysis ofthe various courtship and visual phenotypes associated with this array ofcac mutants demonstrates that Dmca1A calcium channels mediate multiple, separable biological functions; these correlate in part with transcript diversity generated via alternative splicing.

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New perspectives on IL-33 and IL-1 family cytokines as innate environmental sensors

Biochemical Society Transactions ◽

10.1042/bst20170567 ◽

2018 ◽

Vol 46 (5) ◽

pp. 1345-1353 ◽

Cited By ~ 3

Author(s):

Ian C. Scott ◽

D. Gareth Rees ◽

E. Suzanne Cohen

Keyword(s):

Immune Responses ◽

Allergic Inflammation ◽

Proteolytic Processing ◽

Innate Immune ◽

Environmental Sensors ◽

Biological Functions ◽

Soluble Receptors ◽

Direct Sensing ◽

Proteolytic Activities

Interleukin (IL)-1 family cytokines are important initiators of innate immunity and host defence; however, their uncontrolled activities can cause tissue-damaging inflammation. Consequently, IL-1 family cytokines have sophisticated regulatory mechanisms to control their activities including proteolytic processing for their activation and the deployment of soluble receptors and receptor antagonists to limit their activities. IL-33 is a promoter of type 2 immunity and allergic inflammation through its alarmin activity that can rapidly initiate local immune responses by stimulating innate immune cells following exposure to environmental insults, pathogens, or sterile injury. Recent publications have provided new insights into how the range and duration of IL-33 activity is regulated by direct sensing of host-derived and exogenous proteolytic activities as well as oxidative changes during tissue damage. Here, we discuss how this impacts our understanding of the roles of IL-33 in initiating immune responses and the evidence that these sensing mechanisms might regulate the activities of other IL-1 family cytokines and their biological functions. Finally, we discuss translational challenges these discoveries pose for the accurate detection of different forms of these cytokines.

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Analysis of calmodulin fragments and preparation of the peptides containing calcium binding domains by high performance liquid chromatography.

Analytical Sciences ◽

10.2116/analsci.2.287 ◽

1986 ◽

Vol 2 (3) ◽

pp. 287-291

Author(s):

Hiroshi KAWASAKI ◽

Yasuyuki KUROSU ◽

Hisataka KASAI ◽

Tsuneo OKUYAMA ◽

Toshiaki ISOBE

Keyword(s):

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

Calcium Binding ◽

High Performance ◽

Binding Domains

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A novel polyubiquitin chain linkage formed by viral Ubiquitin prevents cleavage by deubiquitinating enzymes

10.1101/756791 ◽

2019 ◽

Author(s):

Hitendra Negi ◽

Pothula Puroshotham Reddy ◽

Chhaya Patole ◽

Ranabir Das

Keyword(s):

Biochemical Properties ◽

Autographa Californica ◽

Polyubiquitin Chain ◽

Deubiquitinating Enzymes ◽

Polyubiquitin Chains ◽

Antiviral Responses ◽

Binding Domains ◽

Central Helix ◽

Ubiquitin Binding ◽

The Stability

ABSTRACTThe Baculoviridae family of viruses encode a viral Ubiquitin gene. Although the viral Ubiquitin is homologous to eukaryotic Ubiquitin (Ub), preservation of this gene in the viral genome indicates a unique function that is absent in the host eukaryotic Ub. We report the structural, biophysical, and biochemical properties of the viral Ubiquitin from Autographa Californica Multiple Nucleo-Polyhedrosis Virus (AcMNPV). The structure of viral Ubiquitin (vUb) differs from Ub in the packing of the central helix α1 to the beta-sheet of the β-grasp fold. Consequently, the stability of the fold is lower in vUb compared to Ub. However, the surface properties, ubiquitination activity, and the interaction with Ubiquitin binding domains are similar between vUb and Ub. Interestingly, vUb forms atypical polyubiquitin chain linked by lysine at the 54th position (K54). The K54-linked polyubiquitin chains are neither effectively cleaved by deubiquitinating enzymes, nor are they targeted by proteasomal degradation. We propose that modification of proteins with the viral Ubiquitin is a mechanism to counter the host antiviral responses.

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Glanzmann thrombasthenia resulting from a single amino acid substitution between the second and third calcium-binding domains of GPIIb. Role of the GPIIb amino terminus in integrin subunit association.

Journal of Clinical Investigation ◽

10.1172/jci117828 ◽

1995 ◽

Vol 95 (4) ◽

pp. 1553-1560 ◽

Cited By ~ 51

Author(s):

D A Wilcox ◽

C M Paddock ◽

S Lyman ◽

J C Gill ◽

P J Newman

Keyword(s):

Amino Acid ◽

Amino Acid Substitution ◽

Calcium Binding ◽

Single Amino Acid Substitution ◽

Single Amino Acid ◽

Amino Terminus ◽

Integrin Subunit ◽

Glanzmann Thrombasthenia ◽

Binding Domains

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S100A13 and S100A6 exhibit distinct translocation pathways in endothelial cells

Journal of Cell Science ◽

10.1242/jcs.115.15.3149 ◽

2002 ◽

Vol 115 (15) ◽

pp. 3149-3158 ◽

Cited By ~ 1

Author(s):

Hsiao-Ling Hsieh ◽

Beat W. Schäfer ◽

Jos A. Cox ◽

Claus W. Heizmann

Keyword(s):

Endothelial Cells ◽

Calcium Binding ◽

Protein Translocation ◽

S100 Proteins ◽

Cellular Functions ◽

Specific Expression ◽

Binding Domains ◽

Cellular Environment ◽

Ef Hands ◽

Physiological Tasks

S100 proteins have attracted great interest in recent years because of their cell- and tissue-specific expression and association with various human pathologies. Most S100 proteins are small acidic proteins with calcium-binding domains — the EF hands. It is thought that this group of proteins carry out their cellular functions by interacting with specific target proteins, an interaction that is mainly dependent on exposure of hydrophobic patches, which result from calcium binding. S100A13, one of the most recently identified members of the S100 family, is expressed in various tissues. Interestingly,hydrophobic exposure was not observed upon calcium binding to S100A13 even though the dimeric form displays two high- and two low- affinity sites for calcium. Here, we followed the translocation of S100A13 in response to an increase in intracellular calcium levels, as protein translocation has been implicated in assembly of signaling complexes and signaling cascades, and several other S100 proteins are involved in such events. Translocation of S100A13 was observed in endothelial cells in response to angiotensin II, and the process was dependent on the classic Golgi-ER pathway. By contrast, S100A6 translocation was found to be distinct and dependent on actin-stress fibers. These experiments suggest that different S100 proteins utilize distinct translocation pathways, which might lead them to certain subcellular compartments in order to perform their physiological tasks in the same cellular environment.

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