Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Protamines”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources
PubMed2006

Common phylogenetic origin of protamine-like (PL) proteins and histone H1: Evidence from bivalve PL genes.

Sperm nuclear basic proteins (SNBPs) can be grouped into three main categories: histone (H) type, protamine (P) type, and protamine-like (PL) type. Protamine-like SNBPs represent the most structurally heterogeneous group, consisting of basic proteins which are rich in both lysine and arginine amino acids. The PL proteins replace most of the histones during spermiogenesis but to a lesser extent than the proteins of the P type. In most instances, PLs coexist in the mature sperm with a full histone complement. The replacement of histones by protamines in the mature sperm is a characteristic feature presented by those taxa located at the uppermost evolutionary branches of protostome and deuterostome evolution, while the histone type of SNBPs is predominantly found in the sperm of taxa which arose early in metazoan evolution; giving rise to the hypothesis that protamines may have evolved through a PL type intermediate from a primitive histone ancestor. The structural similarities observed between PL and H1 proteins, which were first described in bivalve molluscs, provide a unique insight into the evolutionary mechanisms underlying SNBP evolution. Although the evolution of SNBPs has been exhaustively analyzed in the last 10 years, the origin of PLs in relation to the evolution of the histone H1 family still remains obscure. In this work, we present the first complete gene sequence for two of these genes (PL-III and PL-II/PL-IV) in the mussel Mytilus and analyze the protein evolution of histone H1 and SNBPs, and we provide evidence that indicates that H1 histones and PLs are the direct descendants of an ancient group of "orphon" H1 replication-dependent histones which were excluded to solitary genomic regions as early in metazoan evolution as before the differentiation of bilaterians. While the replication-independent H1 lineage evolved following a birth-and-death process, the SNBP lineage has been subject to a purifying process that shifted toward adaptive selection at the time of the differentiation of arginine-rich Ps.

Amino Acid Sequence↗
PubMed1998

Mouse protamine genes are candidate targets for the novel orphan nuclear receptor, germ cell nuclear factor.

Proper expression of the protamine genes is an important event in the terminal differentiation of the male gametes in mammals. Here we present evidence that the novel orphan member of the nuclear receptor gene superfamily, Germ Cell Nuclear Factor (GCNF), may play a role in the regulation of these genes. Previously, we have shown that high-level expression of GCNF mRNA is restricted to spermatids (stages 1-8) in the adult male mouse, which makes it temporally and spatially available to regulate the mouse protamine genes. Furthermore, we have previously identified a sequence to which GCNF can bind, which consists of a direct repeat of the core halfsite AGGTCA with zero base pairs spacing the repeats (DRO). We have identified several genes that contain DRO sequences in their 5' promoter regions, including the protamines. The mouse protamine 1 and 2 (Prm1 and Prm2) genes therefore are potential target genes for GCNF regulation. We show that GCNF binds to one of the two DRO sequences in the Prm1 promoter, and to the DRO sequence in the Prm2 promoter in a specific manner. Furthermore, by using antibodies directed against GCNF, we detect endogenous GCNF in testis nuclear extracts and elutriated round spermatid nuclear extracts in Western blots. Additionally, by using these antibodies in gel-shift assays, we show that this endogenous GCNF can bind to both the Prm1 and Prm2 promoters. This evidence supports the hypothesis that GCNF mediates a novel signaling pathway, two targets of which may be the Prm1 and Prm2 genes in spermatids.

Animals↗
PubMed1984

Inhibition of tumour-induced angiogenesis by systemically administered protamine sulphate.

Systemic administration of protamine sulphate significantly decreased the intensity of angiogenesis induced in X-ray immunosuppressed (BALB/c X DBA/2W) F1 mice by either HEp-2 (human larynx carcinoma) cells or semi-syngeneic splenocytes injected intradermally. In vitro experiments have shown that protamine sulphate markedly decreases the proliferation of human endothelial cells as assessed by 3H-TdR incorporation assay. In contrast, the proliferation of HEp-2 cells was not affected, and only slight inhibition of normal human fibroblasts could be demonstrated. Heparin abolished the inhibitory effect of protamine sulphate, both in vivo and in vitro. These results suggest that the observed inhibitory effect of protamine sulphate on angiogenesis in vivo may be at least partially due to the interaction of this compound with endothelial cells.

Animals↗
PubMedDate not supplied

Marked differences in protamine content and P1/P2 ratios in sperm cells from percoll fractions between patients and controls.

The various sperm cell types present in a simple ejaculate differ in their motility and morphology. However, little is known about the nuclear maturity of these sperm cells and their relationship with morphological and motile characteristics. Protamines are considered a good marker of sperm nuclear maturity since they are added to the DNA in the last stage of spermatogenesis. We have analyzed the P1/P2 ratio and the protamine content of subpopulations of human spermatozoa at different stages of maturation, isolated by density gradient centrifugation of ejaculated spermatozoa obtained from 3 groups of patients from our Assisted Reproduction Unit: 10 men of proven fertility, 12 oligozoospermic men, and 13 asthenozoospermic men. Four different fractions (F2-F5) were collected from the top to the bottom of the Percoll gradient. Differences in the motion and morphology were found between the fractions in each of the groups studied, with fraction F5 being the one with the best morphology and motility. However, no significant differences in the P1/P2 ratio were found between fractions within the same group of samples, indicating that the P1/P2 ratio and the amount of protamines are relatively independent of the morphology and motility of sperm cells. In contrast, statistically significant differences were found in the P1/P2 ratio and in the relative amount of protamines between the 3 groups.

Centrifugation, Density Gradient↗
PubMed1991

Prevention of bioprosthetic heart valve tissue calcification by charge modification: effects of protamine binding by formaldehyde.

Calcification is the principal cause of the clinical failure of bioprosthetic heart valves (BHV). Calcification occurs through an interaction of host and implant factors, mainly younger age and glutaraldehyde pretreatment, respectively. The hypothesis of this work was that an impaired balance between positively and negatively charged amino acids, due to the reaction with Lys and Hyl tissue-collagen residues, expose affinity sites to Ca++. We further hypothesized that regardless of the cause(s) of BHV calcification, positive charge modification of the tissues will prevent their propensity to calcify. Modification of BHV tissue was obtained by covalently binding protamine sulfate, a polybasic peptide, via formaldehyde and subsequent glutaraldehyde tissue crosslinking. Protamine-bound tissue exhibited stability properties (shrinkage temperature and resistance to collagenase digestion) similar to BHV tissue. Protamine-treated tissue was less permeable to Ca++, and reduced staining was observed with positively charged dyes, indicating the presence of positively charged functional groups in the modified tissue. Significant prevention of calcification was exhibited by the p-bound tissue in comparison to BHV tissue, 30.9 and 109 micrograms/mg calcium, respectively, after 30 days of subdermal implants in rats. The modification procedure resulted in stable, covalent links of approximately 10% w/w protamine with undiminished anticalcification properties, even after 1 year storage. The results support our hypotheses, and orthotopical heart valve replacements are required in order to completely evaluate the treatment efficacy and biocompatibility.

Biocompatible Materials↗
PubMed1992

Immunoelectron microscopical distribution of histones H2B and H3 and protamines in the course of mouse spermiogenesis.

We have followed the fine structural distribution of two nucleosomal core histones, H2B and H3, and of protamines in the course of mouse spermiogenesis by means of specific antibodies and ultrastructural immunocytochemistry. Our results demonstrate that the nuclear labeling density of histone H2B decreases during steps 6-8 and then increases again in step 9-10 spermatids, while the labeling for histone H3 is constant throughout this period. In step 12 spermatids, the anti-H2B antibody labels mainly the central area of the nucleus. The first signs of protamine labeling are present in step 12 spermatids, where the gold grains can be found over the periphery of the nucleus. Later on, protamine labeling constantly increases and, by the end of spermiogenesis, the whole nucleus is labeled. We suggest that the morphological and structural differences between the central area and the periphery of mouse spermatids are, at least partly, due to a difference in the protein moiety associated with DNA. The central area, which is peculiar to the mouse and has been previously considered as a focus of chromatin condensation, represents, however, the last nuclear region containing histones and consequently the last area where the substitution of histones by protamines takes place.

Animals↗
PubMed1990

Protamine amount and cross linking in mouse teratospermatozoa and aneuploid spermatozoa.

The level of SH-group oxidation in spermatozoa from the cauda epididymis was measured by a cytofluorometric method in chromosomally normal mice and two chromosome mutants. The first one, a tertiary trisomic karyotype (Ts(1(13]7OH), is characterized by severe oligospermia and high levels (approximately 75%) of malformed spermatozoa. The second, a hybrid between two European feral mouse stocks, is heterozygous for multiple Robertsonian translocations and produces exclusively aneuploid spermatozoa. Neither the severe teratospermiogenesis nor the severe aneuploidy was reflected in total SH-group fluorescence values nor in free SH-group fluorescence. It is concluded that both the production of protamines and protamine cross linking by S-S bridge formation are rather autonomous processes during spermatogenesis because 1) the increased DNA variance of the aneuploid spermatozoa is not reflected in an increased variance of the total and free SH-groups, 2) aneuploidy for the protamine gene carrying chromosome 16 is not reflected by the SH-group values for individual spermatozoa, and 3) protamine production and cross linking are independent of the mild to severe terataspermiogenesis in the tertiary trisomic karyotype.

Aneuploidy↗
PubMed1989

Protamine sulphate-induced proteinuria: the roles of glomerular injury and depletion of polyanion.

It has been claimed that intrarenal injection of polycations results in proteinuria due to neutralization of glomerular basement membrane polyanionic charge without any glomerular morphological changes. To study the effects of polycation infusion on the renal glomerulus, the left kidney of rats was directly injected with protamine sulphate through the renal artery. Urine was collected from each kidney before and after injection, and protein excretion rates were determined. Ninety minutes after completion of the injection both kidneys were perfusion-fixed and the morphology and colloidal iron staining of the kidneys were studied by light and electron microscopy. Intrarenal injection of 0.5, 1, and 2 mg of protamine sulphate produced minimal or mild proteinuria in the majority of animals. Higher doses (5 mg) commonly resulted in decreased protein excretion associated with oliguria. Colloidal iron staining of glomerular polyanionic sites was undiminished when compared with control kidneys. Injection of protamine sulphate resulted in capillary thrombosis and severe damage to both glomerular and tubular epithelium in 6 of 16 kidneys. In the remaining kidneys, milder focal changes were apparent. Although its mechanism of action is unclear, it is apparent that protamine sulphate, even in small doses, is toxic to the cellular components of the glomerulus and tubules, thus accounting for the range of changes observed in renal function.

Animals↗
PubMed1993

An aminoterminally extended P1-protamine variant in the boar.

We have found a minor form of boar sperm P1-protamine with a six amino acid long N-terminal extension. When this sequence was compared with the recently published gene sequence of boar P1-protamine, and with DNA sequences obtained from the boars studied here, a perfect match was found with the 5'-region upstream of the ATG initiation codon of the authentic P1-protamine. Since no extra in-frame ATG initiation codons are present in the 5'-region of the gene, we conclude that the translation of boar P1-protamine variant starts with a non-AUG initiation codon, CUG, which precedes the codon of the first amino acid (serine) of the sequenced variant.

Amino Acid Sequence↗
PubMed1993

Neutrophil activation mediates protamine-induced pulmonary hypertension.

Protamine reversal of heparin anticoagulation can cause catastrophic pulmonary hypertension, systemic hypotension, and hypoxemia. This reaction is thought to be associated with pulmonary sequestration of activated neutrophils. To examine whether this reaction could be prevented by blocking neutrophil activation with NPC 15669 (N-(9H-(2,7-dimethylfluorenyl-9-methoxy)carbonyl)-L-leucine), an inhibitor of Mac-1 adhesion molecule up-regulation, we gave 12 piglets a heparin bolus (300 IU/kg i.v.) followed by protamine (3 mg/kg i.v. over 90 sec) 15 min later. Six of the piglets received NPC 15669 (10 mg/kg i.v. bolus, then 6 mg/kg/hr i.v. infusion) 15 min before the heparin bolus. Two minutes after protamine administration, CD18 (beta-subunit of Mac-1) expression measured by immunofluorescence flow cytometry increased 128 +/- 9% (mean +/- SEM) over preprotamine levels in control piglets but remained unchanged in NPC piglets (99 +/- 2%, P < 0.05). Fifteen minutes after protamine, lung myeloperoxidase activity, an index of neutrophil degranulation, was significantly lower in the NPC group (87.83 +/- 10.04 versus 57.23 +/- 2.59 mumol/10 mg; P < 0.005). NPC 15669 also prevented postreversal pulmonary artery hypertension (158 +/- 30, 150 +/- 20, and 140 +/- 13 versus 91 +/- 7, 91 +/- 18, and 85 +/- 9% preprotamine at Minutes 2, 5, and 10; P < 0.05). Systemic arterial pressure, cardiac output, and circulating neutrophil counts were not different between groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2002

Characterization and phylogenetic utility of the mammalian protamine p1 gene.

We sequenced the protamine P1 gene (ca. 450 bp) from 20 bats (order Chiroptera) and the flying lemur (order Dermoptera). We compared these sequences with published sequences from 19 other mammals representing seven orders (Artiodactyla, Carnivora, Cetacea, Perissodactyla, Primates, Proboscidea, and Rodentia) to assess structure, base compositional bias, and phylogenetic utility. Approximately 80% of second codon positions were guanine, resulting in protamine proteins containing a high frequency of arginine residues. Our data indicate that codon usage for arginine differs among higher mammalian taxa. Parsimony analysis of 40 species representing nine orders produced a well-resolved tree in which most nodes were supported strongly, except at the lowest taxonomic levels (e.g., within Artiodactyla and Vespertilionidae). These data support monophyly of several taxa proposed by morphologic and molecular studies (all nine orders: Laurasiatheria, Cetartiodactytla, Yangochiroptera, Noctilionoidea, Rhinolophoidea, Vespertilionoidea, Phyllostomidae, Natalidae, and Vespertilionidae) and, in agreement with recent molecular studies, reject monophyly of Archonta, Volitantia, and Microchiroptera. Bats were sister to a clade containing Perissodactyla, Carnivora, and Cetartiodactyla, and, although not unequivocally, rhinolophoid bats (traditional microchiropterans) were sister to megachiropterans. Sequences of the protamine P1 gene are useful for resolving relationships at and above the familial level in bats, and generally within and among mammalian orders, but with some drawbacks. The coding and intervening sequences are small, producing few phylogenetically informative characters, and aligning the intron is difficult, even among closely related families. Given these caveats, the protamine P1 gene may be important to future systematic studies because its functional and evolutionary constraints differ from other genes currently used in systematic studies.

Amino Acid Sequence↗
PubMed1994

Pharmacological reduction of brain edema induced by intracarotid infusion of protamine sulphate: a comparison between a free radical scavenger and an AMPA receptor antagonist.

The blood-brain barrier (BBB) of rats was opened by infusing 10 mg protamine sulphate (200 microliters in 30 s) into the right internal carotid artery. Ten minutes later, tirilazad, a 21-aminosteroid (3 mg/kg): NBQX, an AMPA receptor antagonist (5 mg/kg); or dixyrazine, a phenotiazine derivate (10 mg/kg), was administered intravenously and the rats were killed 2 h after protamine infusion. Brain specific gravity was determined in the frontal, parietal and occipital cortex and in the striatum. In separate experiments, serum albumin content was determined in the brain of rats by immunoelectrophoresis 2 h after protamine infusion with or without tirilazad pretreatment. Specific gravity was significantly higher in all of the studied brain regions in rats given tirilazad or NBQX than in those given vehicle or dixyrazine (p < 0.001). A combination of tirilazad and NBQX was significantly more efficient than either drug alone in reducing edema in the occipital cortex (p < 0.05) and more efficient than NBQX alone in the frontal and parietal cortex (p < 0.05). None of the drugs reduced the albumin content in CSF; in addition, tirilazad failed to reduce albumin extravasation in the brain and CSF when given before protamine infusion. We conclude that the anti-edematous effect of tirilazad and NBQX is related to cellular events within the brain and not to a reduction of leakage over the BBB.

Animals↗
PubMed1995

The evolution of protamine P1 genes in dasyurid marsupials.

We report the complete DNA sequences of the protamine P1 gene and flanking regions for 13 species of the marsupial family Dasyuridae. The structure of the protamine locus is conserved in dasyurids and consists of two exons (of lengths 142-151 and 47 bp) separated by an intron (208-240 bp). A key feature of the dasyurid intron is a 38-40 bp duplication found in all species examined to date. This duplication apparently predates the radiation of modern dasyurid lineages and may be homologous to a similar feature in the marsupial mole (Notoryctes). Sequences from a species of Planigale demonstrate that this genus is unique among marsupials in possessing cysteine residues in its protamine P1 molecules. Cysteines may provide enhanced chemical stability for condensed sperm nuclei, a physiological feature that would converge on the common eutherian pattern. Phylogenetic analysis of the protamine genes yields a tree that is largely congruent with previous molecular systematic studies in two areas: (1) There are three main dasyurid lineages corresponding to the Sminthopsinae. Dasyurinae, and Phascogalinae; (2) Dasyurinae and Phascogalinae are sister groups. This study is the first estimate of dasyurid relationships based on a nuclear DNA sequence.

Amino Acid Sequence↗
PubMed1978

Lysosomal activation in mouse skeletal muscle induced by protamine in vitro.

Incubation of mouse skeletal muscle in a physiological Ringer solution containing protamine (60 microgram/ml) at +37 degrees C for 1 h induced ultrastructural changes including proliferation of tubular profiles and vesicles at the I-band level close to the A-I junction, formation of numerous acid phosphatase positive lysosomes in the longitudinal sarcoplasmic reticulum and autophagic vacuolation starting at the level of the A-I junction. Biochemical determination of acid phosphatase in the incubated muscles showed that protamine caused an increase in acid phosphatase activity of about 25% compared to enzyme activities obtained from muscles incubated without protamine at +37 degrees C or with protamine at +4 degrees C. The morphological findings suggest that the vesicles arising adjacent to the A-I junction originate from transverse tubules. Such vesicles, designated as endocytic, may acquire acid phosphatase activity in the longitudinal SR ano be active in an autophagic process resulting in large vacuoles. A causal relationship between endocytosis and lysosomal activation is suggested.

Acid Phosphatase↗
PubMed1977

Protamine induced intracellular uptake of horseradish peroxidase and vacuolation in mouse skeletal muscle in vitro.

The uptake in vitro of horseradish peroxidase (HRP) in mouse skeletal muscle was examined by electron microscopy and chemical determination. In muscles exposed to an HRP solution for 60 min at +37 degrees C, HRP infiltrated the basal lamina of muscle fibres and caused an intense labelling of their sarcolemma. In addition HRP was found within the transverse tubules. Exposure to HRP for 30 min at +37 degrees C followed by HRP together with a polycationic protein (protamine) for 30 min at +37 degrees C caused an intracellular vesicular uptake of HRP. Intracellular HRP was found in numerous vesicles, membrane limited bodies and vacuoles. Protamine also induced focal autophagic vacuolation with progressive muscle fibre degeneration. An intracellular HRP uptake or muscle cell vacuolation could not be detected in the absence of protamine or when the incubation temperature was +4 degrees C. Chemical determination of HRP uptake was in general agreement with the morphological results. The uptake of HRP in the presence of protamine was stimulated at +37 degrees C and blocked at +4 degrees C. The results suggest that in skeletal muscle in vitro intracellular uptake of macromolecules occurs by endocytosis.

Animals↗
PubMed1988

Leakage of blood-retinal barrier due to damaging effect of protamine sulfate on the endothelium.

The effect of the polycations, protamine sulfate and poly-L-lysine, on the blood-retinal barrier of rat retinal vessels were studied by retrograde perfusion through the aorta or by intracarotid perfusion of the polycation followed by the protein tracer, hemoglobin. Protamine sulfate induced swelling of cytoplasmic organelles and diffuse staining of many endothelial cells by tracer molecules which subsequently entered the subendothelial and perivascular areas. Polylysine caused some diffuse staining but no leakage of tracer through the endothelial cell. Occasionally, tracer was found in the interendothelial junction after protamine perfusion. The results indicate that surface charge is important for maintaining membrane integrity of the endothelial cells and that breakdown of the blood-retinal barrier may be due to the cytotoxic effect of protamine on the endothelial cell.

Animals↗
PubMed1986

Oligonucleotides as probes for mammalian protamine mRNAs.

Protamine-like sequences have been identified in poly A(+)mRNAs from mammalian testes by the use of a common, complementary oligonucleotide (GCAGCANCKPTANCKNGCCAT; predicted from the common N-terminal amino acid sequence, MARYRCC, seen in several mammalian P1 protamines [D.J. McKay, B.S. Renaux and G.H. Dixon, Bioscience Reports 5:383-391 (1985)]). This oligonucleotide was utilized to prepare species-specific, primer-extended transcripts for use as Northern blotting probes. Analysis of the mRNA primer-extended transcripts revealed a discrete and similar set of products common to both bull and rat testis mRNAs which were distinct from those obtained from human testis mRNA. Northern analysis of total poly A(+) mRNAs from the corresponding mammalian testis was consistent with these results and suggests that bull and rat protamine mRNAs are more closely related to each other than to human protamine mRNA.

Animals↗
PubMed1985

Functional prokaryotic gene control signals within a eukaryotic rainbow trout protamine promoter.

Following the construction of a series of pSV2-cat derived plasmids containing the chloramphenicol acetyltransferase (CAT) gene under the control of a eukaryotic trout protamine promoter, it was noted that Escherichia coli, transformed with these plasmids, developed resistance to chloramphenicol (CM). This result suggested that the eukaryotic trout protamine promoter possessed significant prokaryotic promoter activity. Modification of the trout protamine promoter region by removing the region containing the eukaryotic Goldberg-Hogness box in the plasmid p525-cat increased the expression of the CAT gene almost to the wild-type level and conferred strong CM resistance. Sequence comparisons of the plasmid series indicate that prokaryotic promoter elements are present in the trout protamine promoter and that their similarity to the prokaryotic promoter consensus sequences and the distance between the two elements is more favourable in p525-cat, the plasmid which confers the greatest CM resistance.

Acetyltransferases↗