Exhibiting rapid polarized growth, the pollen tube delivers the male gametes into the ovule for fertilization in higher plants. To get an overall picture of gene expression during pollen germination and pollen tube growth, we profiled the transcription patterns of 1,536 pollen cDNAs from lily (Lilium longiflorum) by microarray. Among those that exhibited significant differential expression, a c...

The pattern of synthesis of nucleic acids and proteins in the development of the microspore and later during pollen germination and tube growth is discussed. In the pollen grain at the time of anthesis all the proteins that are required for germination and early tube growth are either already present, or if new proteins are synthesized, the messenger RNAs for their synthesis already exist in th...

Potassium antimonite was used to locate calcium in the anthers of Torenia fournieri (Linderniaceae). Abundant calcium precipitates accumulate in the microsporocyte cytoplasm. After meiosis, calcium precipitates are abundant on the microspore wall, as well as the callosic wall of each tetraspore. A large number of calcium precipitates also occur on the outer membranes of the tapetal cells, and i...

Mature, self-incompatible stigmas exposed to cycloheximide for 2 h prior to pollination supported identical germination and growth of both cross and self pollen. Treatment of self-pollinated pistils with cycloheximide resulted in the germination of hitherto inactive pollen after some 2-4 h. Pollen germination and initial tube growth in an in vitro germination medium were not significantly affec...

Pollen mother cells of the lily (Lilium speciosum) were found to have a histone-H1-like protein (PMCP) not detected in other tissues. The PMCP appears from the late S-G(2) period of premeiosis and is present in mature pollen. PMCP and H1 were extracted from pollen mother cells with 5% perchloric acid and isolated by reverse-phase high-performance liquid chromatography. The amino acid compositio...

In Solanaceae, the S-specific interaction between the pistil S-RNase and the pollen S-Locus F-box protein controls self-incompatibility (SI). Although this interaction defines the specificity of the pollen rejection response, the identification of three pistil essential modifier genes unlinked to the S-locus (HT-B, 120K, and NaStEP) unveils a higher degree of complexity in the pollen rejection ...

We have explored methods to achieve excellent results in study of the pollen grain wall by using only one electron microscope, the scanning electron microscope (SEM). While the secondary electron imaging mode , the most common in use, has great value in characterizing the exine surface it is possible to obtain a more comprehensive representation of pollen grain walls by expanding the capability...

Reference ecosystems used in tropical forest restoration lack the temporal dimension required to characterise a mature or intact vegetation community. Here we provide practical ‘palaeo-reference ecosystem’ for eastern Andean forests of Ecuador complement standard ‘reference approach. Pollen assemblages from sedimentary archives recovered Ecuadorian montane are binned into distinct time periods ...

Rho family small GTPases are universal signaling switches in the control of cell polarity in eukaryotic cells. Their polar distribution to the cell cortex is critical for the execution of their functions, yet the mechanism for this distribution is poorly understood. Using a yeast two-hybrid method, we identified RIP1 (ROP interactive partner 1), which belongs to a family of five members of nove...

The major function of pollen is to deliver the sperm nuclei to the embryo sac. It does this by germinating and producing a pollen tube and thus provides a relatively simple developmental system for study. Mutants for many pollen functions are accessible, as it is a haploid cell. Mature pollen was fractionated into diffusible proteins, soluble proteins, and proteins insolubly associated with mem...