I propose a new concept of artificial photosynthetic animal cells as planimal cells. Secondary endosymbiosis, symbiotic algae in animal cells and kleptoplasty evoke algae as the most fascinating autotrophic organisms for the creation of planimal cells. Strategies for the generation of planimal cells include three approaches, cell fusion between algae and animal cells, microinjection of algae into the cytoplasm of a host animal cell and creation of synthetic chimeric chromosomes with both algae and animal genomes. Planimal cells will contribute to overcoming global food problems by reducing energy consumption. Combining planimal cells with medical regeneration techniques will enable photosynthetic therapies. In the future, heterotrophs with planimal cells will support migration to other planets under the harsh conditions through long-distance space travel.
In order to increase the biomass of photosynthetic organisms, upregulation of net CO2 fixation in daytime appears to be a promising approach. This can be attained by improving the turnover of chloroplast enzymes such as ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) or fructose bisphosphate phosphatase (FBPase). In a previous report, the genes for the large and small subunits of cyanobacterial Rubisco were coexpressed in tobacco with either with cyanobacterial chaperone for Rubisco or the carboxysomal CO2 concentrating mechanism (CCM) gene. This resulted in the generation of faster carboxylation of Rubisco and a similar gene expression approach may be adopted into algal hosts in the future. Expression of the cyanobacterial FBPase gene with protein targeting to the chloroplast in Euglena gracilis was reported to increase the wax ester content effectively. Though stable transformation of the oil producing alga Botryococcus braunii race B, is yet to be achieved, genes for key regulatory enzymes in 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway, such as 1-deoxy-D-xylulose 5-phosphate synthase (DXS) or 4-hydroxy-3-methylbut-2-enyl diphosphate reductase (HDR), might be possible targets for genetic modification in this alga. Challenging problems in the transformation of the microalgae, including C. reinhardtii, or those of the macroalgae are discussed herein for the design of transformation aiming at higher yield of biofuel production.
Potato (Solanum tuberosum) is one of the most important food crops in the world which can be used in tissue culture techniques, ranging from in vitro propagation via shoot cultures to regeneration of whole plants from protoplasts. The study was undertaken to determine the influence of node number (single or double) and its orientation (horizontal or vertical) on different growth parameters of potato varieties (Kufri Bahar, Kufri Jyoti, Kufri Lauvkar, Kufri Sindhuri and Kufri Chandramukhi). Six to eight cuttings of double node and single node were inserted vertically and horizontally per bottle at an equilateral distance in MS media without any growth regulators. The study revealed that node number, explants orientation, potato varieties, and their interaction had significant effect on different morphological characters viz., microplant height, number of leaves, nodes, roots as well as dry weight.
The present paper deals with the male meiosis of 17 species covered under 11 genera of the family Poaceae. Three species: Cynodon dactylon (n=8), Sporobolus diander (n=9) and S. helvolus (n=9) are the new cytotypes from world. Further, five species i.e., Avena fatua, A. sativa, C. dactylon, Lolium temulentum var. temulentum and Phalaris minor show anomalous meiotic behavior with the presence of cytomixis, chromatin bridges, laggards, secondary associations and interbivalent connections which lead to low pollen viability.
The existence of intraspecific euploidy (2n=22, 44) in Primula denticulata have been reported in the present study from the higher hills of North-West Himalayas in India. Both the cytotypes showed perfect bivalent formation, regular meiotic course and high pollen fertility. One of the 4x accessions showed a phenomenon of cytomixis and cell fusion resulting to syncytes in meiotic cells. Consequent to chromatin transfer and cell fusion the meiocytes showed various meiotic irregularities, and sterile and heterogeneous pollen grains. The 2x and 4x plants could be distinguished on the basis of some morphometric parameters. The 4x plants are more vigorous growing much taller and possessed gigantism in leaf and floral characters besides increase in size of stomata, trichomes and pollen grains. Analysis of meiotic chromosome pairing in the 4x plants indicate towards the alloploid nature. The presence of cytomixis and syncytes/polyploid meiocytes might have played a role in the production of unreduced large-sized pollen grains facilitating the origin of new polyploids through the formation of such diplogametes. Polyploidy in particularly euploidy, seems to have played a role in the evolution of genus Primula as 38 species depicted polyploid cytotypes including 18 species which showed euploid cytotype.
Long non-coding RNAs (lncRNAs) play key roles in the regulation of biological processes. Salinity inhibits agricultural productivity. The salinity stress tolerance of barley might play important role to understand the regulatory networks. In this study, we performed quantitative real time-PCR (qPCR) and fluorescence in situ hybridization (FISH) to investigate expression levels of two barley lncRNAs—AK363461 and AK370506—and localizations on four barley genotypes (Hasat, Beysehir 99, Konevi 98 and Tarm 92) under 150 mM salt stress conditions during three days germination. Seeds were placed randomly in petri dishes containing filter paper soaked in (a) only H2O (control), (b) 150 mM NaCl for 72 h. RNA extraction were carried out using TriPure® reagent from root and shoot samples. Expression analysis demonstrated salinity effected expression levels of AK363461 and AK370506 on shoots and roots during germination. The expression levels of AK363461 for 150 mM salt applied groups were altered ranged between (log2 −0.82 and 0.80) compared controls. However, the expression levels of AK370506 for 150 mM salt applied groups were altered ranged between (log2 −0.64 and 3.16) compared controls. Comparison of AK363461 and AK370506 expression levels, there was statistically significant difference between barley varieties (p＜0.05). For FISH application, probes were labelled by tetramethylrhodamine (TRITC)–dUTP. The localizations of AK363461 and AK370506 were observed under confocal microscope via FISH on control barley root preparations. Our results is the first direct report to show the relationship between barley lncRNAs and salinity and, also to indicate the localisations of lncRNAs in barley.
The present study deals with the four species of genus Cenchrus L. based on population analysis from different localities in Haryana and adjoining hills of Shiwalik area. These species i.e., C. biflorus, C. ciliaris, C. pennisetiformis and C. setigerus differ from each other morphologically as well as cytologically. In C. biflorus, cytological studies have been made on 23 populations from the study area and three cytotypes (n=16, 17 and 18) are detected. In C. ciliaris, most commonly found species of the genus, 48 populations were studied and four cytotypes with chromosome numbers n=16, 17, 18 and 36 are found. The population analysis revealed that the tetraploid cytotype (n=18) based on x=9 is better adapted as compared to the other three cytotypes. The tetraploid and aneuploid cytotypes are almost morphologically similar, whereas octaploid shows lot of gigantism. All the studied cytotypes of C. ciliaris show meiotic abnormalities. In C. pennisetiformis, two cytotypes with n=17 and 18 are observed, which were found to be morphologically similar with abnormal meiotic course. In this species, 2n=34 is a new chromosome report. The fourth species C. setigerus, also shows similar cytotypes with n=17 and 18, based on the study of 49 populations. These cytotypes are morphologically indistinct and show overlapping morphometric characters.
A translocation heterozygote (without any marker phenotypic trait) is screened in Nigella sativa L. (black cumin) following the exposure of dry seeds (moisture content: 5.0%) to 300 Gy gamma irradiations (one out of twelve). On selfing (53 seeds sown), one heterozygote is detected out of seven survived plants at R2. Compared to 6II formation (2n=12) in PMCs of standard normal plants, the heterozygotes form either a ring or a chain quadrivalents in association to bivalents and univalents (2n=12) in 52.68% (R1) and 30.07% (R2) meiocytes. Ring configuration and adjacent orientation of the multiples are more found to occur predominantly in R1 than R2 heterozygote. Pollen grain fertility and seed setting are found to vary between the translocation heterozygotes irrespective of orientation of the multiples. From the prevalence of ring interchange complexes, it is presumed that the breakpoints are closer to centromere. Furthermore, configurations of the interchange complexes highlight the possibility of two longer pairs of chromosomes to be involved in reciprocal exchanges. A possible genetic control of translocation heterozygote is predicted.
To analyze the karyotypes of five Jatropha species (J. cinerea, J. curcas, J. integerrima, J. multifida, and J. podagrica), fluorescence in situ hybridization (FISH) with a 35S ribosomal RNA gene (rDNA) probe was conducted. FISH analysis of mitotic metaphase chromosomes showed that the numbers of chromosomes and rDNA foci in all species analyzed were conserved, although signal intensities and their locations varied. The conserved karyotypes may be advantageous for the use of J. curcas genome data and for breeding in the progeny of interspecific crosses.
The genus Setaria L. have economically important as a grains and forage. The genus falls under the tribe Paniceae and family Poaceae. The cytological aspects of eight species and 16 accessions have been observed during the present research. S. geniculata (2n=54), S. homonyma (2n=18), and S. italica (2n=36) are the first time reported euploid cytotypes reports from world, whereas, Setaria barbata (2n=54), S. glauca (2n=54), S. pumila (2n=54), S. verticillata (2n=108) are the first cytological reports from Rajasthan. Almost all the species show normal meiosis with minor/negligible abnormalities like secondary associations and univalent. The data presented in the present research shows that the genus Setaria is the result of the multiple suppressor system due to which the genus shows more adaptability and stability than the other genera of family Poaceae.
The present work includes male meiotic studies on 16 populations of Rumex dentatus from different localities of Kashmir Himalaya in diverse altitudinal ranges. The species has been cytologically worked out for the first time from the area. The meiotic chromosome count of n=21 is the first varied chromosome report while as n=60 adds a new cytotype for the species. The basic chromosome numbers for the genus Rumex are reported as 7, 8, 9, and 10. Conforming to x=10, the present investigated taxa are tetraploid and dodecaploid, respectively. The plants belonging to tetraploid cytotypes of R. dentatus were normal in their meiotic course. The accessions of the dodecaploid cytotype showed the phenomenon of cytomixis involving transfer of chromatin material among proximate pollen mother cells (PMCs) and associated meiotic abnormalities like chromatin stickiness, laggards, bridges and multipolarity.
The present investigation recorded male meiotic features on population basis, 30 species in tribe Paniceae belonging to family Poaceae. Four species shows new chromosome counts. These are Brachiaria distachya (n=16), B. ramosa (n=10), B. reptans (n=8), and Echinochloa stagnina (n=9) whereas, Paspalum paspaloides (n=30) shows abnormal meiotic behavior with low pollen fertility.
This study was conducted to test whether the ethanolic extract of the plant Cyperus kyllingia can exert antimitotic effects in actively dividing onion root tip cells, and toxic effects on alive brine shrimp. Onion bulbs and brine shrimps were exposed to solutions of C. kyllingia ethanolic extract at various concentrations for 24 h. Results showed that the extract can block mitosis in onion cells by causing spindle and chromosome damage, which results to mitotic anomalies. In effect, it induces pyknosis and cell death. Moreover, the effects on mitotic index, percentage of C-mitosis, and percentage of other mitotic anomalies are dose-dependent. The test extract can cause dose-dependent lethality in brine shrimp with an estimated LC50 value of 13.47 ppm. The findings indicate that the test plant contains antimitotic and cytotoxic components that may be studied further in animal test systems as possible models of anticancer drugs.
Accession based analysis in Apluda mutica studied from cytologically unexplored and phytogeographically isolated region of Uttarakhand, India revealed the existence of diploid chromosome count of 2n=20, normal meiosis and high pollen fertility. Individuals of three wild accessions however showed the presence of one to two B-chromosomes in 25.64 to 88.06% meiocytes. We here re-record the existence of B-chromosome in species from India. The Bs were noticed to behave differently, either as unpaired or showed regular pairing constituting B-bivalent when paired. B-Bivalent chromosomes also showed different behavior in the meiocytes. In, some cases, Bs disjunct regularly like A-chromosomes. But in some meiocytes they left failed to disjunct and both Bs get included at one pole. It has been inferred that Bs in the presently analysed accessions invariably affect the pollen grain formation and seem to be responsible for reducing pollen fertility.
It has been empirically known that cell walls isolated from giant-celled marine algae, such as Valonia spp., become liable to separate into several layers when transferred from seawater to a diluted buffer, indicating that the cell wall integrity is affected by environmental factors. We established an experimental system for a quantitative evaluation of the separation and investigated the effect of pH on the maintenance of cell wall integrity in V. utricularis. Cell wall strips incubated in artificial seawater (ASW) containing inorganic salts did not separate, whereas all strips incubated in distilled water separated under ultrasonication. Observations by transmission electron microscopy showed that there were gaps between cell wall layers in the cell walls incubated in distilled water; such gaps were not observed under ASW incubation. Separation experiments on cell wall strips incubated in 20 mM Tris or MOPS solutions at various pH showed that the separation of cell wall layers was dependent on environmental pH; namely, they were likely to separate in acidic conditions but not in alkaline conditions. The pH of 20 mM Tris and MOPS at which 50% of all cell wall strips separated into layers was estimated to be 8.4 and 9.2, respectively. These results suggest that the cell wall integrity of the alga is maintained by ionic bonds between the cell wall layers, and the major inorganic ions in seawater might contribute to binding of the cell wall layers, thus preventing separation.
A desynaptic plant (2n=22) is screened from copper oxide nanoparticles (CuO-NPs) treated (dry seeds exposed to 0.25 µg mL−1, 4 h) M1 population (one from 47 plants) of Coriandrum sativum L. (moisture content: 13.60%). Selfed seeds of the marked plant also yield a desynaptic plant (one plant out of five raised; 50 seeds sown) at M2. The mutant plants show enhanced univalent frequency (diplotene-diakinesis: 0–14/cell, metaphase I (MI): 0–20/cell) and reduced chiasma/cell (diplotene-diakinesis: 12.58±0.95 to 12.20±1.34; MI: 12.11±1.13 to 11.64±0.97) than dry and bulk controls (diplotene-diakinesis: univalent frequency 0–4/cell, chiasma/cell 14.77±1.20 to 13.00±0.92; MI 0–4/cell, chiasma/cell 13.85±0.93 to 12.91±0.49). The marked plants document unequal chromosome segregation at anaphase I (AI) (10/12, 9/13, 8/14 and 6/16) and anaphase II (AII) (unequal groups) compared to cytologically balanced separation in controls. Pollen grains fertility is also reduced in the mutant plants (83.36 to 77.76%) than controls (96.91 to 89.88%). Both the M1 and M2 desynaptic plants yield seeds. Results suggest that CuO-NPs can alter meiotic synchrony of genes controlling retention of chiasma formation and maintenance, leading to the development of desynaptic mutant line.
Flagellar movement and mating behavior of the biflagellate gametes of the marine green macroalga, Chaetomorpha spiralis were studied using high-speed video microscopy and field emission scanning electron microscopy (FE-SEM) to clarify the role of flagella during the rapid fertilization of marine green macroalgae. Discharged isogametes always swung their flagella backward during forward swimming. The beat pattern was flagellar beat with undulatory waves produced at the flagellar base being propagated toward the tip. One beat cycle took 15 ms. When the suspension of the gametes was mixed with that of the opposite mating types, the gametes immediately agglutinated to form gamete clumps or mating pairs within 10–20 s. Initial contacts between the two gametes took place at one of the flagellar tips. In the mating gamete pair, the two gametes maintained mutual contact at the flagellar tips and subsequently at their anterior end of the cell bodies. The gametes stuck together, even though they continued to move their flagella and oscillate their cell bodies. Then the two flagella derived from the opposite mating types became a pair and gradually beat synchronously. Finally, the gamete pair lay side-by-side with their longitudinal axes nearly parallel mutually and became a quadriflagellate planozygote. Such features of gamete behavior and their flagellar movement during fertilization resemble those of Ulva.
The snakeheads, freshwater perciform fish are the member of the family Channidae. The karyotype diversification was observed in this species. In this study, we investigate the karyotype and chromosomal characteristic of nucleolar organizing regions (NORs) in Channa marulius (Hamilton, 1822) and C. marulioides (Bleeker, 1851) from Thailand. The metaphase chromosomes were prepared from kidney cells of five male and five female fishes. Conventional and Ag-NOR staining techniques were applied to the chromosomes. The results revealed that: the diploid chromosome number (2n) of C. marulius was 44, fundamental number (NF) was 56, the karyotype formula should be deduced as 2n=Lm4+La6+Lt10+Ma2+Mt22, the NORs are located at the telomeric position of the short arm of chromosome pairs 3 and 4; the 2n of C. marulioides was 38, NF was 68, the karyotype formula should be deduced as 2n=Lm8+La2+Mm2+Ma18+Mt8, the NORs are located at the telomeric position of the short arm of chromosome pairs 10 and 11. The difference of 2n and NF in males and females fish was not observed. The number of Ag-NORs in metaphase cell varies between two and four among the cells in the same sample both in C. marulius and C. marulioides.