scholarly journals PRSS50 is a testis protease responsible for proper sperm tail formation and function

Development ◽  
2021 ◽  
Vol 148 (8) ◽  
Author(s):  
Jason M. Scovell ◽  
Juan C. Bournat ◽  
Adam T. Szafran ◽  
Minerva Solis ◽  
Joshua Moore ◽  
...  

ABSTRACT Multiple morphological abnormalities of the sperm flagella (MMAF) are a major cause of asthenoteratozoospermia. We have identified protease serine 50 (PRSS50) as having a crucial role in sperm development, because Prss50-null mice presented with impaired fertility and sperm tail abnormalities. PRSS50 could also be involved in centrosome function because these mice showed a threefold increase in acephalic sperm (head-tail junction defect), sperm with multiple heads (spermatid division defect) and sperm with multiple tails, including novel two conjoined sperm (complete or partial parts of several flagellum on the same plasma membrane). Our data support that, in the testis, as in tumorigenesis, PRSS50 activates NFκB target genes, such as the centromere protein leucine-rich repeats and WD repeat domain-containing protein 1 (LRWD1), which is required for heterochromatin maintenance. Prss50-null testes have increased IκκB, and reduced LRWD1 and histone expression. Low levels of de-repressed histone markers, such as H3K9me3, in the Prss50-null mouse testis may cause increases in post-meiosis proteins, such as AKAP4, affecting sperm formation. We provide important insights into the complex mechanisms of sperm development, the importance of testis proteases in fertility and a novel mechanism for MMAF.

Author(s):  
Marvin Ferrer

CRES is an inhibitor of a specific member of an enzyme family called serine proteases.  It is thus thought to play a role in enzymatic regulation.  It has been shown to be expressed only in the testes, epididymis, sperm, and gonadotropic cells of the anterior pituitary gland.  Localization of CRES in sperm is an important step in determining its role within sperm.  Previous studies have shown CRES to be localized in the mouse acrosomal cap: a vesicle on the tip of the sperm head which releases its contents upon initial sperm‐egg contact.  The present study shows that developmental analysis of spermatogenesis via immunohistochemistry is incompatible with the conclusion that CRES is localized in the acrosomal cap.   CRES expression begins in the elongating spermatid stage of sperm development; by this point, the acrosomal cap has been completed and it has never been shown that further additions to it can occur.   Western blot and immunogold electron microscopy shows that CRES is localized in the sperm tail.  It is also  possible that further CRES is placed on the outer sperm membranes on the head as it travels through the epididymis, which is a part of the male reproductive tract.


FACE ◽  
2021 ◽  
pp. 273250162110243
Author(s):  
Mikhail Pakvasa ◽  
Andrew B. Tucker ◽  
Timothy Shen ◽  
Tong-Chuan He ◽  
Russell R. Reid

Hedgehog signaling was discovered more than 40 years ago in experiments demonstrating that it is a fundamental mediator of limb development. Since that time, it has been shown to be important in development, homeostasis, and disease. The hedgehog pathway proceeds through a pathway highly conserved throughout animals beginning with the extracellular diffusion of hedgehog ligands, proceeding through an intracellular signaling cascade, and ending with the activation of specific target genes. A vast amount of research has been done elucidating hedgehog signaling mechanisms and regulation. This research has found a complex system of genetics and signaling that helps determine how organisms develop and function. This review provides an overview of what is known about hedgehog genetics and signaling, followed by an in-depth discussion of the role of hedgehog signaling in craniofacial development and carcinogenesis.


1996 ◽  
Vol 135 (3) ◽  
pp. 647-660 ◽  
Author(s):  
G A Smith ◽  
J A Theriot ◽  
D A Portnoy

The ActA protein is responsible for the actin-based movement of Listeria monocytogenes in the cytosol of eukaryotic cells. Analysis of mutants in which we varied the number of proline-rich repeats (PRR; consensus sequence DFPPPPTDEEL) revealed a linear relationship between the number of PRRs and the rate of movement, with each repeat contributing approximately 2-3 microns/min. Mutants lacking all functional PRRs (generated by deletion or point mutation) moved at rates 30% of wild-type. Indirect immunofluorescence indicated that the PRRs were directly responsible for binding of vasodilator-stimulated phosphoprotein (VASP) and for the localization of profilin at the bacterial surface. The long repeats, which are interdigitated between the PRRs, increased the frequency with which actin-based motility occurred by a mechanism independent of the PRRs, VASP, and profilin. Lastly, a mutant which expressed low levels of ActA exhibited a phenotype indicative of a threshold; there was a very low percentage of moving bacteria, but when movement did occur, it was at wild-type rates. These results indicate that the ActA protein directs at least three separable events: (1) initiation of actin polymerization that is independent of the repeat region; (2) initiation of movement dependent on the long repeats and the amount of ActA; and (3) movement rate dependent on the PRRs.


Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 173
Author(s):  
Desirée Bartolini ◽  
Rita Marinelli ◽  
Danilo Giusepponi ◽  
Roberta Galarini ◽  
Carolina Barola ◽  
...  

The metabolism of α-tocopherol (α-TOH, vitamin E) shows marked interindividual variability, which may influence the response to nutritional and therapeutic interventions with this vitamin. Recently, new metabolomics protocols have fostered the possibility to explore such variability for the different metabolites of α-TOH so far identified in human blood, i.e., the “vitamin E metabolome”, some of which have been reported to promote important biological functions. Such advances prompt the definition of reference values and degree of interindividual variability for these metabolites at different levels of α-TOH intake. To this end, a one-week oral administration protocol with 800 U RRR-α-TOH/day was performed in 17 healthy volunteers, and α-TOH metabolites were measured in plasma before and at the end of the intervention utilizing a recently validated LC-MS/MS procedure; the expression of two target genes of α-TOH with possible a role in the metabolism and function of this vitamin, namely pregnane X receptor (PXR) and the isoform 4F2 of cytochrome P450 (CYP4F2) was assessed by immunoblot in peripheral blood leukocytes. The levels of enzymatic metabolites showed marked interindividual variability that characteristically increased upon supplementation. With the exception of α-CEHC (carboxy-ethyl-hydroxychroman) and the long-chain metabolites M1 and α-13′OH, such variability was found to interfere with the possibility to utilize them as sensitive indicators of α-TOH intake. On the contrary, the free radical-derived metabolite α-tocopheryl quinone significantly correlated with the post-supplementation levels of α-TOH. The supplementation stimulated PXR, but not CYP4F2, expression of leucocytes, and significant correlations were observed between the baseline levels of α-TOH and both the baseline and post-supplementation levels of PXR. These findings provide original analytical and molecular information regarding the human metabolism of α-TOH and its intrinsic variability, which is worth considering in future nutrigenomics and interventions studies.


2010 ◽  
Vol 2010 ◽  
pp. 1-4 ◽  
Author(s):  
Heather J. Montgomery ◽  
Andrea L. Dupont ◽  
Hilary E. Leivo ◽  
J. Guy Guillemette

The nitric oxide synthase-like protein fromBacillus cereus(bcNOS) has been cloned, expressed, and characterized. This small hemeprotein (356 amino acids in length) has a mass of 43 kDa and forms a dimer. The recombinant protein showed similar spectral shifts to the mammalian NOS proteins and could bind the substrates L-arginine andNG-hydroxy-L-arginine as well as the ligand imidazole. Low levels of activity were recorded for the hydrogen peroxide-dependent oxidation ofNG-hydroxy-L-arginine and L-arginine by bcNOS, while a reconstituted system with the rat neuronal NOS reductase domain showed no activity. The recombinant bcNOS protein adds to the complement of bacterial NOS-like proteins that are used for the investigation of the mechanism and function of NO in microorganisms.


Blood ◽  
2011 ◽  
Vol 118 (3) ◽  
pp. 795-803 ◽  
Author(s):  
Katia Urso ◽  
Arantzazu Alfranca ◽  
Sara Martínez-Martínez ◽  
Amelia Escolano ◽  
Inmaculada Ortega ◽  
...  

Abstract The nuclear factor of activated T cells (NFAT) family of transcription factors plays important roles in many biologic processes, including the development and function of the immune and vascular systems. Cells usually express more than one NFAT member, raising the question of whether NFATs play overlapping roles or if each member has selective functions. Using mRNA knock-down, we show that NFATc3 is specifically required for IL2 and cyclooxygenase-2 (COX2) gene expression in transformed and primary T cells and for T-cell proliferation. We also show that NFATc3 regulates COX2 in endothelial cells, where it is required for COX2, dependent migration and angiogenesis in vivo. These results indicate that individual NFAT members mediate specific functions through the differential regulation of the transcription of target genes. These effects, observed on short-term suppression by mRNA knock-down, are likely to have been masked by compensatory effects in gene-knockout studies.


Endocrinology ◽  
2011 ◽  
Vol 152 (7) ◽  
pp. 2870-2882 ◽  
Author(s):  
Unmesh Jadhav ◽  
J. Larry Jameson

Steroidogenic factor 1 (SF-1) is essential for the development and function of steroidogenic tissues. Stable incorporation of SF-1 into embryonic stem cells (SF-1-ES cells) has been shown to prime the cells for steroidogenesis. When provided with exogenous cholesterol substrate, and after treatment with retinoic acid and cAMP, SF-1-ES cells produce progesterone but do not produce other steroids such as cortisol, estradiol, or testosterone. In this study, we explored culture conditions that optimize SF-1-mediated differentiation of ES cells into defined steroidogenic lineages. When embryoid body formation was used to facilitate cell lineage differentiation, SF-1-ES cells were found to be restricted in their differentiation, with fewer cells entering neuronal pathways and a larger fraction entering the steroidogenic lineage. Among the differentiation protocols tested, leukemia inhibitory factor (LIF) removal, followed by prolonged cAMP treatment was most efficacious for inducing steroidogenesis in SF-1-ES cells. In this protocol, a subset of SF-1-ES cells survives after LIF withdrawal, undergoes morphologic differentiation, and recovers proliferative capacity. These cells are characterized by induction of steroidogenic enzyme genes, use of de novo cholesterol, and production of multiple steroids including estradiol and testosterone. Microarray studies identified additional pathways associated with SF-1 mediated differentiation. Using biotinylated SF-1 in chromatin immunoprecipitation assays, SF-1 was shown to bind directly to multiple target genes, with induction of binding to some targets after steroidogenic treatment. These studies indicate that SF-1 expression, followed by LIF removal and treatment with cAMP drives ES cells into a steroidogenic pathway characteristic of gonadal steroid-producing cells.


1994 ◽  
Vol 14 (12) ◽  
pp. 8051-8057
Author(s):  
X Zhu ◽  
J E Yeadon ◽  
S J Burden

Although most skeletal muscle genes are expressed at similar levels in electrically active, innervated muscle and in electrically inactive, denervated muscle, a small number of genes, including those encoding the acetylcholine receptor, N-CAM, and myogenin, are expressed at significantly higher levels in denervated than in innervated muscle. The mechanisms that mediate electrical activity-dependent gene regulation are not understood, but these mechanisms are likely to be responsible, at least in part, for the changes in muscle structure and function that accompany a decrease in myofiber electrical activity. To understand how muscle activity regulates muscle structure and function, we used a subtractive-hybridization and cloning strategy to identify and isolate genes that are expressed preferentially in innervated or denervated muscle. One of the genes which we found to be regulated by electrical activity is the recently discovered acute myeloid leukemia 1 (AML1) gene. Disruption and translocation of the human AML1 gene are responsible for a form of acute myeloid leukemia. AML1 is a DNA-binding protein, but its normal function is not known and its expression and regulation in skeletal muscle were not previously appreciated. Because of its potential role as a transcriptional mediator of electrical activity, we characterized expression of the AML1 gene in innervated, denervated, and developing skeletal muscle. We show that AML1 is expressed at low levels in innervated skeletal muscle and at 50- to 100-fold-higher levels in denervated muscle. Four AML1 transcripts are expressed in denervated muscle, and the abundance of each transcript increases after denervation. We transfected C2 muscle cells with an expression vector encoding AML1, tagged with an epitope from hemagglutinin, and we show that AML1 is a nuclear protein in muscle. AML1 dimerizes with core-binding factor beta (CBF beta), and we show that CGF beta is expressed at high levels in both innervated and denervated skeletal muscle. PEBP2 alpha, which is structurally related to AML1 and which also dimerizes with CBF beta, is expressed at low levels in skeletal muscle and is up-regulated only weakly by denervation. These results are consistent with the idea that AML1 may have a role in regulating gene expression in skeletal muscle.


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