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At least 55 records · Page 3Linked to original sources
PubMed1999

The histidine-rich protamine from ostrich and tinamou sperm. A link between reptile and bird protamines.

We have characterized for the first time the proteins of two different species of palaeognathous birds, Struthio camelus australis (ostrich) and Nothoprocta perdicaria sanborni (Chilean tinamou). Similar to what had been previously reported in neognaths, the electrophoretic mobility, amino acid composition, and primary structure of the main protamine (P-II) component of these two species of birds are similar. However, in contrast to neognathous birds, the protamines from paleognaths display a higher electrophoretic mobility and a significantly different amino acid composition and protein sequence. The sperm and the main protamine component P-II from the ostrich reveal structural and compositional characteristics intermediate between neognathous birds and reptiles. The marked differences between the protamines and sperm structure of neognaths and paleognaths provide support to a phylogenetic relationship between neornithine birds in which these two groups represent two separate phylogenetic lines. Furthermore, these results shed some additional light on the controversial origin of birds. They provide further molecular support to the fossil record that suggests that reptiles and birds are closely related.

Alligators and Crocodiles↗
PubMed1994

Disturbances of nuclear condensation in human spermatozoa: search for mutations in the genes for protamine 1, protamine 2 and transition protein 1.

During spermiogenesis, the successive replacement of the somatic histones by basic proteins, the transition proteins and protamines, allows normal sperm nuclear condensation. It was suggested that disturbances in nuclear condensation may result in male infertility. Here we report the first molecular analysis of the structure of three genes which code for germ cell-specific nuclear proteins, namely protamine 1 (PRM1), protamine 2 (PRM2) and transition protein 1 (TNP1) in infertile men with disturbed sperm chromatin condensation. In 36 infertile men whose spermatozoa showed a positive reaction with aniline blue, which is an indication for the presence of histones in the nuclei, the complete nucleotide sequences of the coding regions and 5' and 3' untranslated regions of the three genes were evaluated. In addition, 10 infertile patients with oligoasthenoteratozoospermia were studied in the same way, as well as nine infertile patients whose spermatozoa showed a reduction of the protamine 2 content. We did not detect any mutation in the three genes in any of the patients. We assume that the disturbances in the sperm chromatin condensation of our patients, and those described in the literature, are not primarily due to mutations in the genes for PRM1, PRM2 and TNP1.

Base Sequence↗
PubMed1991

Protamine--the need to determine the dose. Comparison of a simple protamine titration method with an empirical dose regimen for reversal of heparinisation following cardiopulmonary bypass.

A simple method of protamine titration using the Hemochron system was compared with an empirical dose protocol for reversal of heparinisation following cardiopulmonary bypass in 40 patients undergoing elective myocardial revascularisation. Protamine titration revealed a wide range for protamine requirement and resulted in a significant reduction in protamine dose compared with the empirical dose protocol (p less than 0.01). Heparin reversal was assessed as adequate in all patients. The titration technique was easy and straightforward to use in the operating theatre.

Cardiopulmonary Bypass↗
PubMed1991

Cuttlefish sperm protamines. 2. Mass spectrometry of protamines and related peptides.

The sequence of very basic proteins such as protamines (more than 50% arginines) and related peptides has been determined using mass spectrometry in conjunction with Edman degradation. The capabilities of three mass spectrometric (MS) techniques [fast-atom-bombardment (FAB), 252Cf plasma desorption (252CFPD) and electrospray (ES)] have been evaluated on stallion protamine 1, cuttlefish protamine, and the corresponding cleavage peptides. In contrast to FAB-MS and 252Cf PD-MS, ES-MS made possible an easy determination of the molecular mass of the intact protamines (approximately 8 kDa). With ES-MS about 0.2 nmol was sufficient to yield a mass measurement with an accuracy of 0.05%. On peptides smaller than 3500 Da, both FAB-MS and 252Cf PD-MS allowed mass measurements with an accuracy of 0.1%. 252Cf PD-MS appeared more sensitive than FAB-MS by about a factor of 10. FAB-MS is nevertheless particularly interesting since in most cases it produced spectra with intense A-type fragmentation ions which provided reliable primary structure information.

Amino Acid Sequence↗
PubMed1987

Mouse protamine 2 is synthesized as a precursor whereas mouse protamine 1 is not.

The nuclei of mouse spermatozoa contain two protamine variants, mouse protamine 1 (mP1) and mouse protamine 2 (mP2). The amino acid sequence predicted from mP1 cDNAs demonstrates that mP1 is a 50-amino-acid protein with strong homology to other mammalian P1 protamines. Nucleotide sequence analysis of independently isolated, overlapping cDNA clones indicated that mP2 is initially synthesized as a precursor protein which is subsequently processed into the spermatozoan form of mP2. The existence of the mP2 precursor was confirmed by amino acid composition and sequence analysis of the largest of a set of four basic proteins isolated from late-step spermatids whose synthesis is coincident with that of mP1. The sequence of the first 10 amino acids of this protein, mP2 precursor 1, exactly matches that predicted from the nucleotide sequence of cDNA and genomic mP2 clones. The amino acid composition of isolated mP2 precursor 1 very closely matches that predicted from the mP2 cDNA nucleotide sequence. Sequence analysis of the amino terminus of isolated mature mP2 identified the final processing point within the mP2 precursor. These studies demonstrated that mP2 is synthesized as a precursor containing 106 amino acids which is processed into the mature, 63-amino-acid form found in spermatozoa.

Amino Acid Sequence↗
PubMed1988

Haploid-specific transcription of protamine-myc and protamine-T-antigen fusion genes in transgenic mice.

The protamines are small, basic, arginine-rich proteins synthesized postmeiotically in the testes. Analysis of the regulation of synthesis of the protamine mRNA and protein is restricted by the difficulty in culturing and manipulating the cells in which transcription and translation occur. To avoid these problems, we have produced transgenic mice carrying fusion genes in which sequences 5' to the mouse protamine-2 gene have been linked to exons 2 and 3 of the mouse c-myc gene and, separately, to the simian virus 40 (SV40) early region. We show here that the prot.myc gene is correctly regulated; transcription is detected only in the round spermatids. In one family of transgenic mice carrying the 5' protamine-SV40 T-antigen fusion gene, SV40 early-region mRNA accumulated to the highest level in the testes but was also detected in the thymuses, brains, hearts, and preputial glands of the animals. Although we have demonstrated specific transcription of these fusion genes in the round spermatids, we were not able to detect the SV40 T-antigen protein.

Animals↗
PubMed1988

An antiserum against protamines for immunohistochemical studies of histone to protamine transition during human spermiogenesis.

Specific polyclonal antisera have been obtained against total human protamines isolated from purified sperm nuclei. The specificity of antibodies was assessed in immunodotting and immunoblotting assays. In this preliminary report, these specific antibodies were used as probes for in-situ determination of histone to protamine transition during human spermiogenesis. Protamine-containing sites were detected on sections of human testes by light microscopy using the immunoperoxidase technique. As in other mammals, protamines appear and concentrate in condensed nuclei of elongating spermatids, i.e. during the later steps of human spermiogenesis.

Histones↗
PubMed2002

Protamine 1: protamine 2 stoichiometry in the sperm of eutherian mammals.

We have compared the relative proportion of protamine 1 (P1) and protamine 2 (P2) bound to DNA in the sperm of a variety of eutherian mammals to obtain insight into how these two proteins interact in sperm chromatin. Gel electrophoresis (combined with microdensitometry) and high performance liquid chromatography (HPLC) were used to determine the content of the two protamines, and the identity of each protein was confirmed by amino-terminal sequencing or amino acid analysis. The sperm of all species examined contained P1, but P2 was found to be present only in certain species. Unlike the fixed ratio of core histones that package DNA into nucleosomes in all somatic cells, the proportion of P2 present in mature sperm was found to be continuously variable from 0 to nearly 80%. These results show that P1 and P2 do not interact with each other or DNA to form a discrete complex or subunit structure that is dependent upon particular P1/P2 stoichiometries. Data obtained from a number of closely and distantly related species also indicate that while the P2 content of sperm chromatin is allowed to vary over a wide range during the course of evolution, the relative proportion of P1 and P2 are tightly regulated within a genus.

Animals↗
PubMed2005

Oligonucleotide-protamine-albumin nanoparticles: Protamine sulfate causes drastic size reduction.

Nanoparticles prepared by self-assembly from oligonucleotides (ONs), protamine free base, and human serum albumin ("ternary proticles") are spheres of diameters around 200 nm. Substitution of the protamine free base by protamine sulfate leads to proticles of only around 40 nm in diameter with otherwise unchanged properties. The availability of drug delivery systems of very similar composition but grossly different size may be advantageous when dealing with cells which show size-dependent particle uptake. These nanoparticles are promising candidates for ON delivery to cells because of the following reasons: (1) They are stable for several hours in solutions of up to physiological ionic strength; (2) they are efficiently taken up by cells; (3) after cellular uptake, they easily release the ONs even when these are present as phosphorothioates.

Animals↗
PubMed1979

Absorption of protamine-insulin in diabetic patients. I. Preparation and characterization of protamine-125I-insulin.

Protamine-125I-insulin with low specific radioactivity was prepared using 125, 127I-insulin, 0.2 I/mole. The preparations were characterized by disc electrophoresis, isoelectric focusing and analytical gel chromatography in order to evaluate the suitability of 125I-insulin as marker for insulin in protamine-insulin. The stability of the preparations was followed up to 90 days at 4 degrees C. The biological and immunological activity was determined in mice, isolated rat fat cells and by radioimmunoassay. It was concluded that both from a chemical and a biological point of view, the protamine-125I-insulin is a satisfactory preparation that might be used in absorption studies.

Absorption↗
PubMed1975

Pulmonary vasoconstriction produced by protamine and protamine-heparin complex in the isolated cat lung perfused with blood or dextran.

Injections of protamine sulphate, protamine-heparin complex, and the supernatant from this mixture produced a rise in pulmonary artery pressure during constant flow perfusion in the isolated cat lung. The rise in pressure occurred with both blood and dextran perfusates. This suggests that the pulmonary vasoconstriction produced by protamine may be partly due to a direct action on the pulmonary vasculature or to the release of vasoactive substances from the lungs.

Animals↗
PubMed1979

Sequences of large T1 ribonuclease-resistant oligoribonucleotides from protamine mRNA: the overall architecture of protamine mRNA.

Limited T1 ribonuclease digestion of the family of protamine mRNA's purified from rainbow trout testis yields several large oligoribonucleotide fragments ranging in size from 12--54 nucleotides in length. Several of these fragments purified by two dimensional gel electrophoresis contain several G residues and must represent nuclease-resistant, base-paired regions of the mRNA. Sequence analysis of these oligonucleotides by the method of Simoncsits, A., Brownlee, G.G., Brown, R.S., Rubin, J.R. and Guilley, H. (1977) Nature 269: 833-836, shows that these oligoribonucleotides arise from the 5'- and 3'-non-coding regions of the mRNA. Comparisons of the sequences of the large RNA fragment with DNA sequences obtained after cloning double-stranded protamine cDNA in the plasmids pBr322 and pmB9 show precise correspondence of a 54 nucleotide RNA fragment with positions 49--100 from the 3'-poly(A) tract and extending to within 5 nucleotides of the termination codon. Two other RNA fragments of 21 and 25 nucleotides in length arise from the 5'-non-coding region of the message and possess an AUG-sequence at their 3'-termini which is the initiation codon. The presence of distinct by homologous sequences in several sets of large RNA fragments is consistent with the presence of several closely related protamine mRNA's.

Animals↗
PubMed2005

Nontoxic membrane translocation peptide from protamine, low molecular weight protamine (LMWP), for enhanced intracellular protein delivery: in vitro and in vivo study.

Naturally derived, nontoxic peptides from protamine by the authors, termed low molecular weight protamines (LMWPs), possess high arginine content and carry significant sequence similarity to that of TAT, by far the most potent protein transduction domain peptide. Therefore, it was hypothesized that these LMWPs would also inherit the similar translocation activity across the cell membrane, which enables any impermeable species to be transduced into the cells. LMWPs were prepared by enzymatic digestion of protamine, examined their capability of transducing an impermeable protein toxin into the tumor cells by chemical conjugation, and determined cytotoxicity of transduced protein toxin (e.g., gelonin) against cancer cell lines and a tumor-bearing mouse. In vitro results showed that LMWPs could indeed translocate themselves into several mammalian cell lines as efficiently as TAT, thereby transducing impermeable gelonin into the cells by chemical conjugation. In vivo studies further confirmed that LMWP could carry an impermeable gelonin across the tumor mass and subsequently inhibit the tumor growth. In conclusion, the presence of equivalent cell translocation potency, absence of toxicity of peptide itself, and the suitability for low-cost production by simple enzymatic digestion could expand the range of clinical applications of LMWPs, including medical imaging and gene/protein therapies.

Animals↗
PubMed1993

Protamine and protamine-insulins exacerbate the vascular response to injury.

Endothelial cells and smooth muscle cells produce heparinlike compounds that are growth inhibitory for vascular smooth muscle cells, and it has been suggested that these compounds play a regulatory role that is perturbed with vascular injury. Indeed, exogenous heparin preparations effectively suppress smooth muscle cell proliferation following injury imposed on vascular endothelium. We now report that protamine, an agent that binds heparin and negates its anticoagulant properties, has potent stimulatory effects on vascular smooth muscle cell proliferation. The administration of protamine, alone or as part of commonly used insulin preparations, stimulated the proliferation of cultured smooth muscle cells, exacerbated vascular smooth muscle cell proliferative lesions in laboratory rats, and interfered with the growth-inhibitory effects of heparin in culture and in vivo. These results confirm the importance of endogenous heparinlike compounds in arterial homeostasis and may require reconsideration of protamine use following vascular reparative procedures and in diabetics.

Animals↗
PubMed1988

Comparison of the amino acid sequences of human protamines HP2 and HP3 and of intermediate basic nuclear proteins HPS1 and HPS2. Structural evidence that HPS1 and HPS2 are pro-protamines.

Two intermediate nuclear basic proteins HPS1 and HPS2 were isolated from human sperm. They were characterized by their electrophoretic mobility in acid-urea gels, their amino acid composition, and their peptide maps after digestion by endoproteinase Lys-C and by endoproteinase Glu-C. Their amino-terminal amino acid sequences have also been determined. The structural data thus obtained suggest that HPS1 and HPS2 are precursors of human protamines HP2 and HP3.

Amino Acid Sequence↗