Amino Acids In Anthers Research Articles

The effect of cool-pretreatment on the isolated microspore culture and the free amino acid change of anthers in Japonica rice ( Oryza sativa L)

Summary The effect of cool-pretreatment of panicles on the isolated microspore culture and the change in proportion of amino acids in anthers were investigated in japonica rice, and the relationship between free amino acid change and culture response of isolated microspore was suveyed. Cool-pretreatment of panicles for 12–35 days led to an increase of total free amino acid content and the change in proportion of 12 free amino acids. The contents of aspartic acid, threonine, serine, histidine and arginine were increased while the other 7 amino acids, i.e. phenylalanine, glycine, alanine, valine, methionine, leucine, and tyrosine, were decreased. It seemed that 12 days of cool-pretreatment at 6 ± 1 °C were necessary for callusing. High callus formation frequencies were obtained in the cool-pretreatment for 17 to 27 days; the plating efficiencies of 17, 22, and 27 days of cool-pretreatment were 1.17, 1.20, and 1.72 calli per anther, and green plantlet regeneration frequencies were 1.8%, 1.9%, and 3.4%, respectively. However, cool-pretreatment longer than 27 days affected callus initiation and plantlet regeneration.

Further studies on the use of free amino acids in anthers from tulip bulbs cultivar ‘Apeldoorn’ as indicators about cold treatment at 5°C

Twenty-one free amino acids were estimated in freeze-dried anthers from tulip bulbs cooled at 5°C for 12 weeks and subsequently kept at 17°C for 1 week (transport simulation (TS)), and from a control batch kept at 17°C. By comparing the patterns of changes of these amino acids in controlled laboratory trials with the contents in anthers from nine batches of special precooled (12 weeks at 5°C) bulbs from different regions of The Netherlands (“practical samples”), we deduced the following. (1) Arginine, asparagine, glycine, histidine, lysine and tryptophan contents lower than 108, 6, 3, 4, 5 and 3 mmol kg −1, respectively, indicated bulbs that had been precooled. (2) An aspartic acid content lower than 7 mmol kg −1 indicated that cold treatment had lasted for at least 10 weeks. (3) Only aspartic acid constitutes a criterion for duration of treatment.

Changes in the contents of four free amino acids in anthers from tulip bulbs cultivar ‘Apeldoorn’, stored at 5 or 17°C, as criteria related to cold treatment

Asparagine, aspartic acid, glutamic acid and glutamine were estimated in freeze-dried anthers from tulip bulbs precooled at 5°C for 12 weeks and subsequently at 17°C for 1 week (transport simulation), and from a control batch kept at 17°C. Based on the patterns of changes of these 4 free amino acids, we deduced the following: (1) the asparagine content could be an indicator of cold treatment: it was less than 7 mmol kg −1 for cold-stored bulbs and higher than 15 mmol kg −1 for the control; (2) an aspartic acid content of 3–6 mmol kg −1 could indicate that cold treatment had lasted for at least 11 weeks. These criteria apply to laboratory-scale tests; (3) the contents of glutamine and glutamic acid cannot be used as criteria of cold treatment because they are similar in treated and control bulbs during 1 week of transport simulation.

Relationship between pollen degeneration and amino acids, especially proline, in male-sterile Japanese radish ( Raphanus sativus L. var. longipinnatus Bailey)

Proline has been found to occur in only small quantities in sterile anthers, whereas it is abundant in fertile ones. However, the cause-and-effect relationship between proline and pollen degeneration was not clear. The present study was undertaken to solve this problem, using male-sterile and male-fertile plants of Japanese radish. The content of free amino acids in anthers of both plants was analyzed at the pollen mother cell (PMC) stage and at the mature (or degenerated) pollen stage. At the PMC stage there was little difference in proline content between sterile and fertile anthers, suggesting that proline is not involved in the condition of the anthers which leads to either sterility or fertility. At the mature (or degenerated) pollen stage, every amino acid occurred more abundantly in fertile anthers than in sterile ones. Fertile anthers at this stage contained much more proline than at the PMC stage. On the other hand, the quantities of amino acids in sterile anthers were small, and the decrease of proline was dramatic. These small amounts of amino acids, including proline, may be a result of pollen degeneration, because at this stage the collapse of pollen is so complete that only dried anther walls are anatomically observed. Filaments of sterile stamens contained much proline, suggesting its accumulation in situ due to the prevention of transfer to the destroyed anther.

Free amino acids of Nicotiana alata anthers during development in vivo

The variation of free amino acids in anthers and pollen of Nicotiana alata Link et Otto has been examined during pollen development in vivo. The purpose was to find clues for optimizing an in vitro medium for cultivation of haploid plantlets from N. alata pollen. The quantitatively most important amino acids were proline, glutamic acid/glutamine, alanine and aspartic acid/asparagine. These exhibited similar patterns of variation during pollen development: first maximum (0.5 to 1.7 μmol per flower) at mitosis, then decrease during early binucleate stage (0.6 to 2.0 mmol per flower). Other amino acids were found in much smaller quantities (max 0.25 μmol per flower).

Amino acids in anthers of Milo and in cytoplasmic genetic male sterile sorghums (Sorghum bicolor L. Moench) of Indian origin

Amino acid composition of proteins from anthers of milo and Indian origin male steriles were determined. Comparison of amino acid between A and B lines showed lower contents of histidine, threonine, glutamic acid, glycine, leucine and phenylalanine and higher contents of alanine, serine, proline and tyrosine in line A compared to line B. Alanine content in anthers of A lines was more than two fold higher than that in the anthers from B lines. Marked differences in amino acid composition of anthers of A and B lines are suggestive of their involvement in male sterility. Cytoplasmic male steriles of Indian origin M35-1A and M31-2A showed greater similarity but differed from milo, VZM2A and B.

Studies on the Developmental Physiology in Rice Pollen : II. Relation between the amino acid metabolism and the structural changes in pollens

The relation between the changes of amino acid metabolism and the structural alteration with special reference to the behavior of the vegetative and generative nucleus during pollen development were studied. At the one nuclear period no distinct difference was found in amino acid composition between anthers and other plant tissues and organs. In binuclear period in which a microspore nucleus divided into two nuclei, a vegetative nucleus and a generative one, the proline content comes to higher than that of other amino acids in anthers. At the middle of binuclear period proline was found to occupy about 20% of all amino acid content, indicating that the special feature of amino acid metabolism in pollen begins under the occurrence of a vegetative and a generative nucleus. At the beginning of trinuclear period having one vegetative nucleus and two sperm nuclei, proline was found to reach an amazing high content as like 50% of total amino acids in anthers. Thus accumulated synthesis of proline, known as the characteristic of amino acid metabolism in pollen, appears established at the trinuclear period. Activity of nuclei in pollen was examined by the size of nucleolus after acetocarmine staining since it has been considered as an indicator of the physiological activity of nucleus. At the one nuclear period, a large nucleolus just like as that of meristematic cells was found in a microspore nucleus. In the time when a microspore nucleus divided into a vegetative and generative nucleus, a nucleolus of the former was larger than that of the latter. With the occurrence of two sperm nuclei, the size of a nucleolus in vegetative nucleus began to decrease and the configuration of nucleus was obscure and its nucleolus disappeared in the day before flowering. On the contrary, nucleoli of two sperm nuclei derived from a generative one, were large and clear since then. On the basis of these results, it was assumed that the establishment of the special feature of amino acid metabolism in pollens and the occurrence of generative or sperm nucleus are correlated each other in time, and the accumulated production of proline may be regulated by the sperm nuclei, judging from the behavior of nucleolus

Male Sterility Caused by Cooling Treatment at the Young Microspore Stage in Rice Plant : VIII. Free amino acids in anthers

[in Japanese]

Histochemical studies on the cytoplasmic male-sterility of sugar beets, with special reference to the hydroeenion concentration, carbohydrates and amino acids in anthers.

The present paper is devoted to the observation of histochemical phenomena in anther tissue of cytoplasmic maie-sterile sugar beets contrasted with those in normal strains. I. Hydrogen-ion concentration in anther tissue. Based on several observations using pH indicators (Methyl red or Brom thymol blue), following conclusions could be drawn(Table 1, 2, 3 and Fig. 1, 2, 3). In the early stage of microsporogenesis, the pH values in anther tissue of both rnormal and malesterile types are rather high ranging: from 6.6 to 7.0. As the age of anthers of normal types advances to the microspore stage, the pH values decrease to about 6.2, then they increase agnin to about 6.8 at the D. ollen-grrain stage, and, at the anthesis, the pH values decrease to about 6.2. On the other hand, the pH values observed in anthers of male-sterile types never show such zig-zag curves as those of normal strains during the microsporogenesis, but gradually decrease to about 6.2 at the anthesis.