Průhledy ; sv. XVI
Vydání první 187 stran : ilustrace (převážně barevné), tabulky ; 21 cm
- MeSH
- biologická evoluce MeSH
- ekologie MeSH
- rostliny MeSH
- rozmnožování MeSH
- sexualita MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- populární práce MeSH
- Konspekt
- Obecná biologie
- NLK Obory
- biologie
The journey undertaken by the pollen tube in angiosperms to reach the deeply embedded female gametophyte for fertilization involves persistent guidance by the female gametophyte and accurate perception of the signals by the pollen tube. Several ovule-secreted peptides have been identified. Nevertheless, there are no exact findings on how these signals are perceived by the pollen tube. As a novel approach, we have improvised a modified SIV (semi-in vivo) technique, SIV-PS (SIV pollen tube secretome), to perform gel-free LC-MS/MS for high-throughput analysis of pollen-tube-secreted proteins. Our approach has led to the identification of over 1400 protein groups. Among them are pollen-tube-secreted ligands and receptor proteins representing potential male components in perceiving ovule-emitted cues for guidance. The present article reviews the missing link in pollen tube perception and showcases the improvised SIV-PS as a tool for high-throughput and targeted study of the pollen tube secretome.
Mature pollen represents an extremely resistant quiescent structure surrounded by a tough cell wall. After its hydration on stigma papillary cells, pollen tube growth starts rapidly. Massive metabolic changes are likely to be accompanied by changes in protein phosphorylation. Protein phosphorylation belongs among the most rapid post-translational modifications. To date, only Arabidopsis thaliana and tobacco (Nicotiana tabacum) mature pollen have been subjected to phosphoproteomic studies in order to identify the phosphoproteins present. In the present mini-review, Arabidopsis and tobacco datasets were compared with each other. The representation of the O-phosphorylated amino acids was compared between these two datasets, and the putative pollen-specific or pollen-abundant phosphopeptides were highlighted. Finally, the phosphorylation sites common for both Arabidopsis and tobacco phosphoproteins are listed as well as the phosphorylation motifs identified.
The transition between the quiescent mature and the metabolically active germinating pollen grain most probably involves changes in protein phosphorylation status, since phosphorylation has been implicated in the regulation of many cellular processes. Given that, only a minor proportion of cellular proteins are phosphorylated at any one time, and that phosphorylated and nonphosphorylated forms of many proteins can co-exist within a cell, the identification of phosphoproteins requires some prior enrichment from a crude protein extract. Here, we have used metal oxide/hydroxide affinity chromatography (MOAC) based on an aluminum hydroxide matrix for this purpose, and have generated a population of phosphoprotein candidates from both mature and in vitro activated tobacco pollen grains. Both electrophoretic and nonelectrophoretic methods, allied to MS, were applied to these extracts to identify a set of 139 phosphoprotein candidates. In vitro phosphorylation was also used to validate the spectrum of phosphoprotein candidates obtained by the MOAC phosphoprotein enrichment. Since only one phosphorylation site was detected by the above approach, titanium dioxide phosphopeptide enrichment of trypsinized mature pollen crude extract was performed as well. It resulted in a detection of additional 51 phosphorylation sites giving a total of 52 identified phosphosites in this set of 139 phosphoprotein candidates.
- MeSH
- 2D gelová elektroforéza MeSH
- chromatografie afinitní metody MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- fosfoproteiny analýza chemie izolace a purifikace MeSH
- fosforylace MeSH
- molekulární sekvence - údaje MeSH
- proteom analýza chemie MeSH
- pyl chemie MeSH
- rostlinné proteiny analýza chemie MeSH
- sekvence aminokyselin MeSH
- sekvenční seřazení MeSH
- tabák chemie MeSH
- titan MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Rapid changes of protein phosphorylation play a crucial role in the regulation of many cellular processes. Being post-translationally modified, phosphoproteins are often present in quite low abundance and tend to co-exist with their unphosphorylated isoform within the cell. To make their identification more practicable, the use of enrichment protocols is often required. The enrichment strategies can be performed either at the level of phosphoproteins or at the level of phosphopeptides. Both approaches have their advantages and disadvantages. Most enriching strategies are based on chemical modifications, affinity chromatography to capture peptides and proteins containing negatively charged phosphate groups onto a positively charged matrix, or immunoprecipitation by phospho-specific antibodies.In this article, the most up-to-date enrichment techniques are discussed, taking into account their optimization, and highlighting their advantages and disadvantages. Moreover, these methods are compared to each other, revealing their complementary nature in providing comprehensive coverage of the phosphoproteome.
- MeSH
- barvení a značení MeSH
- chromatografie afinitní MeSH
- fosfoproteiny chemie izolace a purifikace metabolismus MeSH
- fosforylace MeSH
- hmotnostní spektrometrie MeSH
- imunoprecipitace MeSH
- peptidové fragmenty chemie izolace a purifikace metabolismus MeSH
- posttranslační úpravy proteinů MeSH
- proteom chemie izolace a purifikace metabolismus MeSH
- proteomika MeSH
- rostlinné proteiny chemie izolace a purifikace metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
