scholarly journals Deciphering the tissue specificity of the protein secretory pathway in humans

2016 ◽  
Author(s):  
Amir Feizi ◽  
Francesco Gatto ◽  
Mathias Uhlen ◽  
Jens Nielsen

AbstractProteins that are components of the secretory machinery form a cellular pathway of paramount importance for physiological regulation, development and function of human tissues. Consistently, most secretory pathway components are ubiquitously expressed in all tissues. At the same time, recent studies identified that the largest fraction of tissue-specific proteins consists of secreted and membrane proteins and not intracellular proteins. This suggests that the secretory pathway is distinctively regulated in a tissue-specific fashion. However, a systematic analysis on how the protein secretory pathway is tuned in different tissues is lacking, and it is even largely unexplored if the secretome and membrane proteome differs in, for example, posttranslation modifications across tissues. Here, analyzing publically available transcriptome data across 30 human tissues, we discovered the expression level of key components previously categorized as housekeeping proteins were specifically over-expressed in a certain tissue compared with the average expression of their corresponding secretory pathway subsystem (e.g. protein folding). These extreme genes define an exceptional fine-tuning in specific subnetworks, which neatly differentiated for example the pancreas and liver from 30 other tissues. Moreover, the subnetwork expression tuning correlated with the nature and number of post translational modification sites in the pancreas or liver-specific secretome and membrane proteome. These patterns were recurrently observed also in other tissues, like the blood, the brain and the skeletal muscle. These findings conciliate both the housekeeping and tissue-specific nature of the protein secretory pathway, which we attribute to a fine-tuned regulation of defined subnetworks in order to support the diversity of secreted proteins and their modifications.

2000 ◽  
Vol 72 (3) ◽  
pp. 355-363 ◽  
Author(s):  
Vadim T. Ivanov ◽  
Oleg N. Yatskin ◽  
Olga A. Kalinina ◽  
Marina M. Philippova ◽  
Andrei A. Karelin ◽  
...  

Systematic analysis of several tissue extracts for peptide components followed by bioactivity studies leads to formulation of the concept of "tissue-specific peptide pools". According to that concept the endogenous proteolysis of proteins with well-established functions, such as hemoglobin, actin, and cellular enzymes in tissues leads to formation of the sets (or pools) of bioactive peptides. The sets are tissue-specific on one hand and conservative in a given tissue at normal conditions on the other. The content and the composition of pool components are sensitive both to pathologies linked with alterations of tissue metabolism and to prolonged physiological changes. In vivo formation of fragments of functional proteins includes several consecutive proteolytic stages inside the cells and further release of bioactive compounds into the surrounding medium. The effects of pool components take place predominantly at tissue and cellular levels, their effects being related to stimulation or inhibition of cell growth, induction of cell differentiation, and death. The above-mentioned features lead to the proposal that the main in vivo function of components of tissue-specific peptides is maintenance of tissue homeostasis, i.e., the normal ratio of functional, dividing, differentiating, and dying cells of tissues. Components of tissue-specific peptide pools display several features distinguishing them from "classical" peptide hormones and neuromediators. Summarizing, a novel peptidergic regulatory system is considered.


Genes ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 449 ◽  
Author(s):  
JiaRui Li ◽  
Lei Chen ◽  
Yu-Hang Zhang ◽  
XiangYin Kong ◽  
Tao Huang ◽  
...  

Tissue-specific gene expression has long been recognized as a crucial key for understanding tissue development and function. Efforts have been made in the past decade to identify tissue-specific expression profiles, such as the Human Proteome Atlas and FANTOM5. However, these studies mainly focused on “qualitatively tissue-specific expressed genes” which are highly enriched in one or a group of tissues but paid less attention to “quantitatively tissue-specific expressed genes”, which are expressed in all or most tissues but with differential expression levels. In this study, we applied machine learning algorithms to build a computational method for identifying “quantitatively tissue-specific expressed genes” capable of distinguishing 25 human tissues from their expression patterns. Our results uncovered the expression of 432 genes as optimal features for tissue classification, which were obtained with a Matthews Correlation Coefficient (MCC) of more than 0.99 yielded by a support vector machine (SVM). This constructed model was superior to the SVM model using tissue enriched genes and yielded MCC of 0.985 on an independent test dataset, indicating its good generalization ability. These 432 genes were proven to be widely expressed in multiple tissues and a literature review of the top 23 genes found that most of them support their discriminating powers. As a complement to previous studies, our discovery of these quantitatively tissue-specific genes provides insights into the detailed understanding of tissue development and function.


Antioxidants ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1578
Author(s):  
Tao Shi ◽  
Paulien E. Polderman ◽  
Marc Pagès-Gallego ◽  
Robert M. van Es ◽  
Harmjan R. Vos ◽  
...  

Reversible cysteine oxidation plays an essential role in redox signaling by reversibly altering protein structure and function. Cysteine oxidation may lead to intra- and intermolecular disulfide formation, and the latter can drastically stabilize protein–protein interactions in a more oxidizing milieu. The activity of the tumor suppressor p53 is regulated at multiple levels, including various post-translational modification (PTM) and protein–protein interactions. In the past few decades, p53 has been shown to be a redox-sensitive protein, and undergoes reversible cysteine oxidation both in vitro and in vivo. It is not clear, however, whether p53 also forms intermolecular disulfides with interacting proteins and whether these redox-dependent interactions contribute to the regulation of p53. In the present study, by combining (co-)immunoprecipitation, quantitative mass spectrometry and Western blot we found that p53 forms disulfide-dependent interactions with several proteins under oxidizing conditions. Cysteine 277 is required for most of the disulfide-dependent interactions of p53, including those with 14-3-3q and 53BP1. These interaction partners may play a role in fine-tuning p53 activity under oxidizing conditions.


2000 ◽  
Author(s):  
Robert Lane Smith

Abstract Articular cartilage provides diarthrodial joints with a loading-bearing surface that ensures functional motility. The physical characteristics of articular cartilage originate with the highly organized matrix of extracellular macromolecules that provide structural elements to the tissue. The matrix specialization rests with specific proteins produced by the cartilage cells, the chondrocytes that undergo extensive post-translational modification through addition of sulfated glycosaminoglycan and oligosaccharides. The matrix proteins fall into three major categories, the collagens, the proteoglycans and the glycoproteins, with each group contributing unique properties to cartilage form and function.


2020 ◽  
Vol 16 (34) ◽  
pp. 2853-2861
Author(s):  
Yanli Li ◽  
Rui Yang ◽  
Limo Chen ◽  
Sufang Wu

CD38 is a transmembrane glycoprotein that is widely expressed in a variety of human tissues and cells, especially those in the immune system. CD38 protein was previously considered as a cell activation marker, and today monoclonal antibodies targeting CD38 have witnessed great achievements in multiple myeloma and promoted researchers to conduct research on other tumors. In this review, we provide a wide-ranging review of the biology and function of the human molecule outside the field of myeloma. We focus mainly on current research findings to summarize and update the findings gathered from diverse areas of study. Based on these findings, we attempt to extend the role of CD38 in the context of therapy of solid tumors and expand the role of the molecule from a simple marker to an immunomodulator.


Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 336
Author(s):  
Roberta Melchionna ◽  
Paola Trono ◽  
Annalisa Tocci ◽  
Paola Nisticò

Human tissues, to maintain their architecture and function, respond to injuries by activating intricate biochemical and physical mechanisms that regulates intercellular communication crucial in maintaining tissue homeostasis. Coordination of the communication occurs through the activity of different actin cytoskeletal regulators, physically connected to extracellular matrix through integrins, generating a platform of biochemical and biomechanical signaling that is deregulated in cancer. Among the major pathways, a controller of cellular functions is the cytokine transforming growth factor β (TGFβ), which remains a complex and central signaling network still to be interpreted and explained in cancer progression. Here, we discuss the link between actin dynamics and TGFβ signaling with the aim of exploring their aberrant interaction in cancer.


Antioxidants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 486
Author(s):  
Valerio Ciccone ◽  
Shirley Genah ◽  
Lucia Morbidelli

The vascular endothelium consists of a single layer of squamous endothelial cells (ECs) lining the inner surface of blood vessels. Nowadays, it is no longer considered as a simple barrier between the blood and vessel wall, but a central hub to control blood flow homeostasis and fulfill tissue metabolic demands by furnishing oxygen and nutrients. The endothelium regulates the proper functioning of vessels and microcirculation, in terms of tone control, blood fluidity, and fine tuning of inflammatory and redox reactions within the vessel wall and in surrounding tissues. This multiplicity of effects is due to the ability of ECs to produce, process, and release key modulators. Among these, gasotransmitters such as nitric oxide (NO) and hydrogen sulfide (H2S) are very active molecules constitutively produced by endotheliocytes for the maintenance and control of vascular physiological functions, while their impairment is responsible for endothelial dysfunction and cardiovascular disorders such as hypertension, atherosclerosis, and impaired wound healing and vascularization due to diabetes, infections, and ischemia. Upregulation of H2S producing enzymes and administration of H2S donors can be considered as innovative therapeutic approaches to improve EC biology and function, to revert endothelial dysfunction or to prevent cardiovascular disease progression. This review will focus on the beneficial autocrine/paracrine properties of H2S on ECs and the state of the art on H2S potentiating drugs and tools.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Giulietta M. Riboldi ◽  
Irene Faravelli ◽  
Takaaki Kuwajima ◽  
Nicolas Delestrée ◽  
Georgia Dermentzaki ◽  
...  

AbstractSMN is a ubiquitously expressed protein and is essential for life. SMN deficiency causes the neurodegenerative disease spinal muscular atrophy (SMA), the leading genetic cause of infant mortality. SMN interacts with itself and other proteins to form a complex that functions in the assembly of ribonucleoproteins. SMN is modified by SUMO (Small Ubiquitin-like Modifier), but whether sumoylation is required for the functions of SMN that are relevant to SMA pathogenesis is not known. Here, we show that inactivation of a SUMO-interacting motif (SIM) alters SMN sub-cellular distribution, the integrity of its complex, and its function in small nuclear ribonucleoproteins biogenesis. Expression of a SIM-inactivated mutant of SMN in a mouse model of SMA slightly extends survival rate with limited and transient correction of motor deficits. Remarkably, although SIM-inactivated SMN attenuates motor neuron loss and improves neuromuscular junction synapses, it fails to prevent the loss of sensory-motor synapses. These findings suggest that sumoylation is important for proper assembly and function of the SMN complex and that loss of this post-translational modification impairs the ability of SMN to correct selective deficits in the sensory-motor circuit of SMA mice.


2021 ◽  
Vol 7 (5) ◽  
pp. 328
Author(s):  
María Dolores Pejenaute-Ochoa ◽  
Carlos Santana-Molina ◽  
Damien P. Devos ◽  
José Ignacio Ibeas ◽  
Alfonso Fernández-Álvarez

Protein O-mannosyltransferases (Pmts) comprise a group of proteins that add mannoses to substrate proteins at the endoplasmic reticulum. This post-translational modification is important for the faithful transfer of nascent glycoproteins throughout the secretory pathway. Most fungi genomes encode three O-mannosyltransferases, usually named Pmt1, Pmt2, and Pmt4. In pathogenic fungi, Pmts, especially Pmt4, are key factors for virulence. Although the importance of Pmts for fungal pathogenesis is well established in a wide range of pathogens, questions remain regarding certain features of Pmts. For example, why does the single deletion of each pmt gene have an asymmetrical impact on host colonization? Here, we analyse the origin of Pmts in fungi and review the most important phenotypes associated with Pmt mutants in pathogenic fungi. Hence, we highlight the enormous relevance of these glycotransferases for fungal pathogenic development.


Sign in / Sign up

Export Citation Format

Share Document