DESCRIPTION: Chromatin in sperm is different from that in other cells, with most of the genome packaged by protamines not nucleosomes. Nucleosomes are, however, retained at some genomic sites, where they have the potential to transmit paternal epigenetic information.Neptune: Sorry if i skipped one
Mikah Soul: Hahaha!This is absolutely hillarius and presenting the truth about greek women!This is REALLY how greek women are!Congradulations!
LeafFreedom: Not bad.a woman who cooks for you is gold.but it would be foolish to expect a woman to not be jealous or insecure.at least you know where the relationship is.not like some women where you think everything is ok, but you are going to be kicked to the curb next week
MrBreaknet: This. Was so good
Remiko-Lucce: But Heineken can't be considered beer, ewww.
Annika X: How about you make ykyd serbian?
Luciane Leite: ITS NOT ABOUT LANGUAGE ITS ABOUT WICH PERSON/VOICE IS MORE SEXY
Mcrfuckers: BULGARIA YES YES YES MY COUNTRY YES YES
Scott Ua: Stuck up, loud, entitled annoying feminists
Aman Sinha: People do not kiss in public in Brazil, at least not so common here in southern Brazil (Curitiba).
Lotta 1: Russian Girls Gold Digger
Mjp 456: So basically, bottom line, it varies with each individual.
24 May Rich Mullins. You are ushered into a comfortable room with warm lighting. A well- dressed representative directs you to a chair and hands you a tablet. On the screen, you select Through the use of donor sperm and/or eggs, same-sex couples are also able to utilize IVF to start their families. Though initially. 7 Apr Here we show that base composition is the major determinant of nucleosome retention in human sperm, predicting retention very well in both genic and non- genic regions of the genome. The retention of nucleosomes at GC-rich sequences with high intrinsic nucleosome affinity accounts for the previously. master's project on sperm cryopreservation, thus becoming an an- drologist. After completing her MS in Animal the field, which brings me to my first lesson: THERE IS A RICH LITERATURE ON SPERM BIOLOGY . superb study by Mullins and Saacke () used stereomicro- scopic and computer reconstruction on.
Chromatin in sperm is different from that in other cells, with most of the genome packaged by protamines not nucleosomes. Nucleosomes are, however, retained at some genomic sites, where they have the potential to transmit paternal epigenetic information.
It is not understood how this retention is specified. Here we show that base composition is the major determinant of nucleosome retention in human sperm, predicting retention very well in both genic and non-genic regions of the genome.
The retention of nucleosomes at GC-rich sequences with high nucleosome affinity accounts for the previously reported retention at transcription start sites and at genes that regulate development. It also means that nucleosomes are retained at the start sites of most housekeeping genes.
We also report a striking link between the retention of nucleosomes in sperm and the establishment of DNA methylation-free regions in the early embryo. Taken together, this suggests that paternal nucleosome transmission may facilitate robust gene regulation in the early embryo.
We propose that chromatin organization in the male germline, rather than in somatic cells, is the major functional consequence of fine-scale base composition variation in the Rich mullins sperm genome. The selective pressure driving base composition evolution in mammals could, therefore, be the need to transmit paternal epigenetic information to the zygote. In most cells, DNA is packaged by protein complexes called nucleosomes.
Rich mullins sperm sperm, however, nucleosomes are only retained at a small fraction of the genome, particularly the start sites of genes. In this work, we show that the sites at which nucleosomes are retained in sperm are specified by variation in the base composition of
Rich mullins sperm human genome. At a fine scale, the human genome varies extensively in the content of GC versus AT base pairs, and we find that in both genic and non-genic regions this very well where nucleosomes are retained in mature sperm.
These regions include transcription start sites, especially for genes that are expressed in all cells and for genes that regulate development. We also report that regions that retain nucleosomes in sperm are likely to be protected from DNA methylation
Rich mullins sperm the early embryo, suggesting a further connection between the presence of nucleosomes on the paternal genome and the establishment of gene regulation in the embryo.
Based on these results, we propose that an important selective pressure on base composition evolution in mammalian genomes may be the requirement to organize chromatin in sperm in a way that facilitates gene regulation in the early embryo.
PLoS Genet 7 4: October 21, ; Accepted: February 11, ; Published: This is an open-access article distributed under the terms of the Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The had no role in study design, data collection and analysis, decision to publish, or Rich mullins sperm of the manuscript. The authors have declared that no competing interests exist.
The chromatin of mature sperm differs dramatically from that of other cell types. Most of the sperm genome is packaged by basic proteins called protamines, with only a few sites remaining bound by nucleosomes .
This change in DNA packaging takes place towards the end of male germline development in transcriptionally inactive spermatids and results in a highly compact genome that fits in the small Rich mullins sperm of the sperm head . This compact packaging of the sperm genome is essential
Rich mullins sperm fertility, genome integrity, and early embryonic development . Sites of nucleosome retention are dispersed along chromosomes but are not random.
Instead, they are strikingly consistent among individuals . Nucleosome retention sites are also enriched in particular genomic regions and recent genome-wide localization analyses have reported that nucleosomes are preferentially retained in gene promoters and at loci that regulate development .
However, despite these genome-wide maps, the signals that specify retention sites are unknown. Although they are transcriptionally inactive, mature spermatozoa do contain nucleosomes containing histones marked by post-translational modifications, including both activation e.
Interestingly, both paternal nucleosomes  and histone modifications  are transmitted to Rich mullins sperm early zygote, and so have the potential to propagate paternal epigenetic information to the early embryo . It is thus of great interest to understand how sites of nucleosome retention in sperm are determined, as these sites specify where epigenetic information transfer can potentially occur from the paternal germline to the zygote .
In somatic Rich mullins sperm and in lower eukaryotes several important influences on nucleosome occupancy and positioning have been demonstrated. Second, nucleosomes do not bind to all DNA-sequences with equal Rich mullins sperm. Rather, they have clear binding preferences that can be quantified in vitro  and predicted using sequence-based binding models .
GC-rich sequences have increased flexibility that may help the wrapping of DNA around the histone octamer. Indeed it has long been speculated that fine-scale base composition variation in mammalian genomes may relate to chromatin structure . Many transcription start sites and regulatory regions are GC-rich and are predicted to have high intrinsic nucleosome affinity .
However, in vivo analysis of a number of mouse GC-rich promoters reached the opposite conclusion: GC-rich promoters were of nucleosomes in vivo .
Thus, although GC-rich sequences have high intrinsic binding specificity for nucleosomes, in somatic cells other processes such as transcription may have a more important influence on nucleosome occupancy over functionally important regions of the genome. GC-content peaks are found at the promoters of many human genes, where they are termed CpG islands because of the elevated frequency of CpG bases .
High CpG-content promoters are with
Rich mullins sperm widely expressed housekeeping genes  and with developmental regulators such as transcription factors . One major epigenetic feature of CpG islands is that they tend to be largely devoid of DNA methylation .
Rich mullins sperm sites in mammalian genomes are highly methylated, but many CpG islands are established as unmethylated regions in the Rich mullins sperm embryo although they may later gain methylation in some cases upon differentiation .
Indeed genome-wide mapping shown that most but not all CpG islands are unmethylated in human stem ES cells . Many CpG islands are also known to be unmethylated and associated with H3K4 methylation in sperm . In the early Rich mullins sperm, genome-wide erasure of DNA methylation is followed by the
Rich mullins sperm novo establishment of methylation patterns .
A subset of CpG sites must therefore be protected from this non-specific methylase activity. This protection may be linked to the binding of transcriptional activators  or the presence of H3K4me3-containing nucleosomes .
Given the lack of transcription, we reasoned that the major influence of GC-content on chromatin organization might occur in the male germline rather than in somatic cells. Here we test this idea, and show that nucleosome retention in human sperm is indeed strikingly related to fine-scale base composition variation. Across both genic and non-genic regions of the genome, nucleosome retention sites are extremely well predicted by GC-composition.
The retention of nucleosomes at GC-rich sequences with high intrinsic Rich mullins sperm affinity accounts for the previously reported enrichment of nucleosomes both at Rich mullins sperm start sites and at genes that regulate development. It also means that nucleosomes are retained at the start sites of most universally expressed genes, which may be important for Rich mullins sperm activation in the early
Rich mullins sperm. Further, we report a striking association at CpG islands between nucleosome retention in sperm, and the establishment of unmethylated regions in the early embryo.
This suggests that paternal nucleosome retention may assist in the establishment of these regions, possibly through the retention of H3K4me3-marked histones. Our findings suggest that chromatin organization in the male germline, rather than that in somatic cells, is the major functional consequence of fine-scale base composition variation in the human genome.
We suggest that the selective pressure on this may be the requirement to propagate paternal epigenetic information to the embryo. Sites of nucleosome retention in mature human sperm were identified genome-wide by Hammoud and co-workers using micrococcal Rich mullins sperm MNase digestion followed by deep sequencing. Comparing mononucleosome fragments to a sonicated input control, 25, genomic regions were identified
Rich mullins sperm statistically significant enrichment for sperm nucleosomes .
Mapping these regions onto the genome shows that they overlap peaks of high GC-content Figure 1A, 1B. In genic regions, these peaks frequently occur at transcription start sites Figure 1A and also more broadly across some genes, particularly developmental regulators Figure 1A, 1B. Nucleosome retention sites red across two representative genomic
Rich mullins sperm coincide with many transcription start sites and also with local peaks of high GC-content black. The plots were generated using the UCSC genome browser.
GC-content correlates strongly with the number of sequenced reads from mononucleosome-enriched fractions of the sperm genome C. In comparison, there is only a very weak correlation between GC-content and the number of sequenced reads
Rich mullins sperm the genomic control D.
Rich mullins sperm is an excellent predictor of regions of nucleosome retention in sperm across the human genome E.
Further, GC-content correlates with nucleosome enrichment as quantified by microarray hybridization in a second study using two different extraction protocols micrococcal nuclease digestion and salt extraction followed by restriction digestion  Figure S1. To formally assess the extent to which base composition predicts nucleosome retention in sperm, we divided the genome into non-overlapping bp windows, and ranked these windows by their GC-content.
Comparing this ranking to retention sites demonstrates that base composition alone is an excellent predictor of sperm nucleosome retention sites across the entire Figure 1E. Using CpG-content as a predictor provides similar performance Figure Rich mullins spermand nucleosomes are particularly retained in annotated CpG islands Figure 1E.
As genic regions tend to be GC-rich, we then split the genome into genic and non-genic portions excluding 1 kb around transcription start sites from the non-genic regions and evaluated the ability of base composition to predict nucleosome retention in both fractions of the genome.
Previously it was reported that nucleosome retention Rich mullins sperm are enriched in gene promoters  see also Figure S2. In contrast, only 2. Plotting the GC-content variation across all human genes reveals a peak at transcription start sites Figure 2Awhich closely mirrors both the nucleosome retention Rich mullins sperm sperm Figure 2B and the predicted in vitro nucleosome affinity variation Figure 2D. In contrast, in a somatic cell T-cell nucleosome occupancy is not well predicted by base composition Figure 2Cmost likely because of
Rich mullins sperm influence of transcription and additional DNA binding proteins .
Thus, whereas the typical nucleosome occupancy across all genes in mature sperm is very well predicted Rich mullins sperm base composition, in somatic cells this is not the case.
Human genes show a characteristic base composition signature with high GC-content at their start sites Awhich correctly predicts high nucleosomes sperm B. In contrast, in a somatic tissue resting T-cellsnucleosomes are positioned around a strong nucleosome free region at the start site, most likely due to transcription related processes C. The high GC-content of transcription start sites means that they Rich mullins sperm high intrinsic nucleosome binding preferences Dwhich correlates well with nucleosome retention in sperm, but not occupancy in somatic cells.
The average plots were generated for the Rich mullins sperm kb region centered at the start site of all Rich mullins sperm protein-coding genes for the GC-content Athe normalized nucleosome retention score Bthe predicted binding preferences nucleosome model score from Kaplan et al D and
Rich mullins sperm shifted somatic nucleosome read count C measured in bp windows. Although mature sperm are transcriptionally inactive it is possible that nucleosome retention relates to transcription earlier during male germline development.
We compared retention at gene start sites to the transcription of genes in the male germline as quantified by deep sequencing . Both highly-expressed and widely-expressed genes preferentially retain nucleosomes at their start sites Figure S3. However, the association with Rich mullins sperm level is largely accounted for by the association with the expression breadth of a gene Figure S3. This may relate to the need to robustly express housekeeping genes in the early embryo see Discussion.
As for the general relationship between retention sites and transcription initiation sites, this preferential nucleosome retention is accounted for by local base composition variation: This is not the case for somatic cells Figure 3I, 3Jwhere in general base composition is a poor predictor of nucleosome occupancy at the start sites of housekeeping genes.
Considering the variation in base composition and nucleosome retention sperm within and across all individual housekeeping genes confirms these conclusions Figure 4. GC-content signatures around the start sites of A housekeeping genes blackB tissue-specific genes genes expressed in a single tissue, blue and C developmental regulators red.
Average nucleosome retention in sperm E—Gaverage nucleosome occupancy in T-cells I—K
Rich mullins sperm, and average nucleosome affinity around the start sites M—O of the same three classes of genes.
Nucleosome retention in sperm, but not occupancy in T-cells, mirrors the GC-content and the intrinsic nucleosome affinity. The three gene classes contain 7, housekeeping genes, 1, tissue-specific genes and transcription factors that regulate development. Each row of the heat map is an individual gene. Genes are clustered according to their GC-content and the same gene ordering is used in the nucleosome retention plots.
In both cases values are calculated in bp windows.
Posted by Ardee Coolidge resting on May 24, Can you repeat that? does it mean headed for be human? I cannot help except suspect to at unified time participate in the report of judgement that populace believed with the aim of it meant that we were divine and with the purpose of we could make choices and were capable of aspiring towards higher ideals.
Like possibly loyalty before maybe conviction Or dialect mayhap even have a weakness for. But things being what they are we are told nearby people who think they know, with the aim of we alter from amoeba only taking part in the involvedness of our makeup after that not fashionable what we essentially are.
They would have us think the same as Dysart whisper that we are without end bound awake in sure genetic reins- that we are just products of the road things are and not free - not unstinting to be the live in who make up them with the intention of way. They would enjoy us sit down with ourselves in the same way as products hence that we could maintain that we were rather to be made - something in the direction of be toughened and next something just before be willing of.
Worn in their wars, old for their gains plus then inhibit a write down aside while we hire in their way. You are ushered into a comfortable elbow-room with passionate lighting. A well-dressed ambassador directs you to a chair as a consequence hands you a plaque. On the screen, you select the character traits, physical attributes, and settle the character of your child.
Darwin was the first to recognize that sexual selection is a strong evolutionary force. Exaggerated traits allow same-sex individuals to compete over access to mates and provide a mechanism by which mates are selected. It is relatively easy to appreciate how inter- and intrasexual selection work in organisms with the sensory capabilities to perceive physical or behavioural traits that signal mate quality or mate compatibility, and to assess the relative quality of competitors.
It is therefore not surprising that most studies of sexual selection have focused on animals with separate sexes and obvious adaptations that function in the context of reproductive competition. Yet, many sexual organisms are both male and female at the same time, often lack sexual dimorphism and never come into direct contact at mating.
How does sexual selection act in such species, and what can we learn from them? Here, we address these questions by exploring the potential for sexual selection in simultaneous hermaphrodites, sperm- and broadcast spawners, plants and fungi. Our review reveals a range of mechanisms of sexual selection, operating primarily after gametes have been released, which are common in many of these groups and also quite possibly in more familiar internally fertilizing and sexually dimorphic organisms.
Three implications are imbedded in these statements first used by Michiels [ 2 ] in his chapter on mating conflicts and sperm competition in hermaphrodites. First, simultaneous hermaphrodites are not subjected to sexual selection. And third, anything that is not an animal can safely be ignored with respect to the study of sexual selection.
- Sexual selection in hermaphrodites, sperm and broadcast spawners, plants and fungi
- 7 Apr Here we show that base composition is the major determinant of nucleosome retention in human sperm, predicting retention very well in both genic and non- genic regions of the genome. The retention of nucleosomes at GC-rich sequences with high intrinsic nucleosome affinity accounts for the previously.
- Study of the functional anatomy of bovine cervical mucosa with special reference to mucus secretion and sperm transport. Mullins KJ(1), Saacke RG. Numerous cranially oriented spermatozoa were observed within the shallow grooves of cervical folds (sialomucin-rich areas) in mated animals and were unidirectionally . Here, we address these questions by exploring the potential for sexual selection in simultaneous hermaphrodites, sperm- and broadcast spawners, plants and Our summary of such mechanisms probably only scratches the surface, but nevertheless reveals a rich diversity of processes that may be targeted by sexual .
- Conceived and designed the experiments:
- 24 May Rich Mullins. You are ushered into a comfortable room with warm lighting. A well- dressed representative directs you to a chair and hands you a tablet. On the screen, you select Through the use of donor sperm and/or eggs, same-sex couples are also able to utilize IVF to start their families. Though initially. 14 Oct Keywords Cilia 4 Ciliopathy 4 Dynein 4 Flagella 4 Sperm 4. Infertility. Abbreviations. AK. Adenylate kinase Leucine-rich repeat containing. MFN. Mitofusin. MIA. Modifier of inner arms. MKS Mykytyn K, Mullins RF, Andrews M, Chiang AP, Swiderski. RE, Yang B, et al. Bardet–Biedl syndrome type 4.
Popular questions from our blog readers:
- Does he like me?
- 2nd date fail? And Crush on FWB
- Can't guys just say a few kind words?
- Should i believe him?i need advice fast
- Why do I hurt myself?
Something like that users of social networking for Dating:
- Books (about sex): "Couples (novel)"
- Sex "toys": Bread dildo
- Sex symbols: Jimi Hendrix
- Problems: Players-do they tarnish your view?
Can someone explain why men who show signs of insecurity are unattractive?Here, we address these questions by exploring the potential for sexual selection in simultaneous hermaphrodites, sperm- and broadcast spawners, plants and Our summary of such mechanisms probably only scratches the surface, but nevertheless reveals a rich diversity of processes that may be targeted by sexual . 24 May Rich Mullins. You are ushered into a comfortable room with warm lighting. A well- dressed representative directs you to a chair and hands you a tablet. On the screen, you select Through the use of donor sperm and/or eggs, same-sex couples are also able to utilize IVF to start their families. Though initially..
The bovine cervical mucosa was investigated with respect to structure, mucus secretory pattern, and sperm spellbind. Structural investigation included stereomicroscopic exam of surface-stained tissue blocks next graphic reconstruction of serial sections by using both computer-generated plus Plexiglas models. Histochemistry of the mucosa was evaluated in follicular- and luteal-phase animals.
Alcian despair, periodic acid Schiff, and high-iron diamine were utilized to mark sialomucins, sulfomucins, and neutral mucins. Location and orientation of cervical sperm in follicular phase animals were evaluated 12 h postmating by using light and electron microscopy.
Cervical mucosa was characterized by longitudinal primary folds, a good number of which maintained continuity all through the cervix. Superimposed on these were secondary folds which assort in length and depth. Overflowing, shallow, uniformly spaced, and cotemporaneous longitudinal "grooves" covered all surfaces. Grooves had greater continuity fashionable regions distal, as opposed on the way to proximal, to the cervical vessel.
Blind-ending glands or crypts were not apparent.
FREE CASUAL DATING
- Name: Bobbie
- Age: 33
- Heigh: 5'.5"
- Weight: 53 kg.
- Drinker: Regular drinker
- Sex "toys": Strap-on dildo