scholarly journals Transcriptome and translatome changes in germinated pollen under heat stress uncover roles of transporter genes involved in pollen tube growth

2020 ◽  
Author(s):  
Laetitia Poidevin ◽  
Javier Forment ◽  
Dilek Unal ◽  
Alejandro Ferrando
Author(s):  
Laetitia Poidevin ◽  
Javier Forment ◽  
Dilek Unal ◽  
Alejandro Ferrando

ABSTRACTPlant reproduction is one key biological process very sensitive to heat stress and, as a consequence, enhanced global warming poses serious threats to food security worldwide. In this work we have used a high-resolution ribosome profiling technology to study how heat affects both the transcriptome and the translatome of Arabidopsis thaliana pollen germinated in vitro. Overall, a high correlation between transcriptional and translational responses to high temperature was found, but specific regulations at the translational level were also present. We show that bona fide heat shock genes are induced by high temperature indicating that in vitro germinated pollen is a suitable system to understand the molecular basis of heat responses. Concurrently heat induced significant down-regulation of key membrane transporters required for pollen tube growth, thus uncovering heat-sensitive targets. We also found that a large subset of the heat-repressed transporters is specifically up-regulated, in a coordinated manner, with canonical heat-shock genes in pollen tubes grown in vitro and semi in vivo, based on published transcriptomes from Arabidopsis thaliana. Ribosome footprints were also detected in gene sequences annotated as non-coding, highlighting the potential for novel translatable genes and translational dynamics.


1995 ◽  
Vol 73 (4) ◽  
pp. 583-589 ◽  
Author(s):  
James A. Winsor ◽  
Andrew G. Stephenson

Pollen tube growth rates and pollen tube attrition were examined in Cucurbita pepo plants grown in an experimental garden. Two separate studies were performed utilizing controlled hand-pollinations. First, female flowers were hand-pollinated and collected at intervals over a 22-h period. Examination of stained pollen tubes in these pistils under reflected UV light revealed variation in growth rate: after approximately 7 h, the fastest growing pollen tubes grew at nearly twice the rate of the mass of the pollen tubes. The faster growing tubes reached the top of the ovary well ahead of most of the pollen tubes. Second, density of pollen application was varied and counts of germinated pollen and pollen tubes were made at four points from the stigmatic surface to the receptacle. Attrition was high for all pollen densities, but significantly higher rates occurred at high and medium densities just below the stigmatic surface. Pollen tube attrition at other points in the pistil was associated with constrictions in the stylar tissue and possibly with levels of nutrients in the pistil. Key words: Cucurbita pepo, pollen competition, pollen tube attrition.


1983 ◽  
Vol 10 (2) ◽  
pp. 137 ◽  
Author(s):  
HS Saini ◽  
M Sedgley ◽  
D Aspinall

Wheat plants (cv. Gabo) otherwise grown at 20°C were subjected to a temperature of 30°C for 3 days at the onset of meiosis in the anthers. Control plants were maintained at 20°C throughout development. Serial sections through the heat-stressed ovaries just prior to anthesis showed that a third contained abnormal embryo sacs. Abnormalities ranged from the complete absence of an embryo sac accompanied by reduced nucellus development, to small embryo sacs that contained the full complement of cells. No abnormalities were observed in control ovaries. Following pollination with fertile pollen, heat-stressed stigmas had similar numbers of germinated pollen grains to non-stressed controls but there were fewer tubes reaching the ovary. In 7% of the stressed pistils, no pollen tube reached the ovary. Callose was deposited in some of the inhibited pollen grains and tubes that showed abnormal growth. It is concluded that heat stress during meiosis in wheat can reduce yield by causing abnormal ovary development, which results in reduced pollen tube growth and seed set.


1989 ◽  
Vol 58 (3) ◽  
pp. 515-521 ◽  
Author(s):  
Goro OKAMOTO ◽  
Ikuo SHIBUYA ◽  
Miwa FURUICHI ◽  
Kazuo SHIMAMURA

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Biying Dong ◽  
Qing Yang ◽  
Zhihua Song ◽  
Lili Niu ◽  
Hongyan Cao ◽  
...  

AbstractMature pollen germinates rapidly on the stigma, extending its pollen tube to deliver sperm cells to the ovule for fertilization. The success of this process is an important factor that limits output. The flavonoid content increased significantly during pollen germination and pollen tube growth, which suggests it may play an important role in these processes. However, the specific mechanism of this involvement has been little researched. Our previous research found that hyperoside can prolong the flowering period of Abelmoschus esculentus (okra), but its specific mechanism is still unclear. Therefore, in this study, we focused on the effect of hyperoside in regulating the actin-depolymerizing factor (ADF), which further affects the germination and growth of pollen. We found that hyperoside can prolong the effective pollination period of okra by 2–3-fold and promote the growth of pollen tubes in the style. Then, we used Nicotiana benthamiana cells as a research system and found that hyperoside accelerates the depolymerization of intercellular microfilaments. Hyperoside can promote pollen germination and pollen tube elongation in vitro. Moreover, AeADF1 was identified out of all AeADF genes as being highly expressed in pollen tubes in response to hyperoside. In addition, hyperoside promoted AeADF1-mediated microfilament dissipation according to microfilament severing experiments in vitro. In the pollen tube, the gene expression of AeADF1 was reduced to 1/5 by oligonucleotide transfection. The decrease in the expression level of AeADF1 partially reduced the promoting effect of hyperoside on pollen germination and pollen tube growth. This research provides new research directions for flavonoids in reproductive development.


Genes ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 249
Author(s):  
Weimiao Liu ◽  
Liai Xu ◽  
Hui Lin ◽  
Jiashu Cao

The growth of plant cells is inseparable from relaxation and expansion of cell walls. Expansins are a class of cell wall binding proteins, which play important roles in the relaxation of cell walls. Although there are many members in expansin gene family, the functions of most expansin genes in plant growth and development are still poorly understood. In this study, the functions of two expansin genes, AtEXPA4 and AtEXPB5 were characterized in Arabidopsis thaliana. AtEXPA4 and AtEXPB5 displayed consistent expression patterns in mature pollen grains and pollen tubes, but AtEXPA4 also showed a high expression level in primary roots. Two single mutants, atexpa4 and atexpb5, showed normal reproductive development, whereas atexpa4atexpb5 double mutant was defective in pollen tube growth. Moreover, AtEXPA4 overexpression enhanced primary root elongation, on the contrary, knocking out AtEXPA4 made the growth of primary root slower. Our results indicated that AtEXPA4 and AtEXPB5 were redundantly involved in pollen tube growth and AtEXPA4 was required for primary root elongation.


2021 ◽  
Vol 288 ◽  
pp. 110390
Author(s):  
Radosav Cerović ◽  
Milica Fotirić Akšić ◽  
Milena Đorđević ◽  
Mekjell Meland

Sign in / Sign up

Export Citation Format

Share Document