Genetic analysis of Caenorhabditis elegans pry-1/Axin suppressors identifies genes involved in reproductive structure development, stress responses, and aging

The Axin family of scaffolding proteins regulates a wide array of developmental and post-developmental processes in eukaryotes. Studies in the nematode Caenorhabditis elegans have shown that the Axin homolog PRY-1 plays essential roles in multiple tissues. To understand the genetic network of pry-1, we focused on a set of genes that are differentially expressed in the pry-1-mutant transcriptome and are linked to reproductive structure development. Knocking down eight of the genes (spp-1, clsp-1, ard-1, rpn-7, cpz-1, his-7, cdk-1, and rnr-1) via RNA interference efficiently suppressed the multivulva phenotype of pry-1 mutants. In all cases, the ectopic induction of P3.p vulval precursor cell was also inhibited. The suppressor genes are members of known gene families in eukaryotes and perform essential functions. Our genetic interaction experiments revealed that in addition to their role in vulval development, these genes participate in one or more pry-1-mediated biological events. Whereas four of them (cpz-1, his-7, cdk-1, and rnr-1) function in both stress response and aging, two (spp-1 and ard-1) are specific to stress response. Altogether, these findings demonstrate the important role of pry-1 suppressors in regulating developmental and post-developmental processes in C. elegans. Given that the genes described in this study are conserved, future investigations of their interactions with Axin and their functional specificity promises to uncover the genetic network of Axin in metazoans.

Growth and yield performance of strawberry (Fragaria ananassa) under various doses of vermicompost and NPK fertilizers grown at rooftop of Charfasson area in the southern parts of Bangladesh

A pot experiment was carried out on the rooftop of a building at Charfasson town Bhola to evaluate the growth and yield performance of strawberry (Fragaria ananassa) as influenced by different doses of vermicompost and inorganic fertilizers in the winter season of 2020-2021. Each pot was filled with ten kg soil and arranged in a completely randomized design having seven treatments with three replications. Treatments were T1: Control (-VC), T2: 5 t VC/ha, T3: 10 t VC/ha, T4: 15 t VC/ha, T5: 20 t VC/ha, T6: 25 t VC/ha, and T7: 50% RDF NPK (40 - 15-25 kg/ha). Different agronomic parameters were measured at the intervals of 30, 60, 90, and 120 days after sowing of seeds. All the treatments of vermicompost showed better responses in agronomic parameters than the control treatment. Among them, T5 treatment tends to show significantly (p<0.05) higher plant height (18.5 cm), number of the leaf (54/plant), root length (15.50 cm), first flowering (at 61 days), fruit length (5.75 cm), fruit diameter (13.75 cm), number of fruits (15/plant), the average weight of fruit (14.50 g), the fresh yield of fruits (13.59 t/ha), fresh weight of root (10.41 g/plant), fresh weight of reproductive structure (3.12 g/plant), weight of the dry reproductive structure (3.12 g/plant) and benefit-cost ratio (9.37). T6 treatment showed significantly (p<0.05) higher leaf area (49.00 cm2), fresh weight of petiole (4,61 g/plant), the weight of dry root (2.20 g/plant), weight of dry leaf (5.87 g/plant), weight of dry petiole (1.42 g/plant) and weight of dry biomass (12.48 g/plant). T2, T3 and T4 treatments showed significantly (p<0.05) higher growth than T7 treatment. The overall findings revealed that the application of vermicompost (20 t/ha) in the strawberry plant might be a suitable method in rooftop gardening to achieve its better agronomic and yield parameters in the southern parts of Bangladesh. Dhaka Univ. J. Biol. Sci. 30(2): 283-292, 2021 (July)

The Male Reproductive Structure and Spermatogenesis of Trypophloeus Klimeschi Eggers (Coleoptera: Curculionidae: Scolytinae)

The authors have requested that this preprint be withdrawn due to author disagreement.

Weltrichia magna sp. nov., a new record for the Middle Jurassic of Oaxaca, México

The Jurassic locality San Juan Mixtepec (Zorrillo Formation in the state of Oaxaca) contains fossil plants of the order Bennettitales, mainly of the genus Zamites, as well as reproductive structures of the genera Williamsonia, Williamsoniella and Weltrichia, but male reproductive structures of the latter genus are scarce and almost restricted to the south of Mexico; they have also been reported in the Triassic of the north of Mexico. Here we report a new record for this locality and a new species of male reproductive structure of the genus Weltrichia. We recovered half of an adpression in fine-grained sandstone with the positive and negative of the adaxial part of the male reproductive structure, which when open measures 22.6 cm in diameter. A reconstruction suggests the presence of ten centrifugal rays that become thinner towards the acute apex and are fused in a central basal cup. The structure exhibits complete centrifugal rays with basal structures that are interpreted as insertion sites for pollen sacs. We employed acetate peel, mechanical separation and hydrofluoric acid (HF) maceration techniques for extraction of anatomical samples. We compared 13 morphological and 10 anatomical characters with previous records from localities in México, Europe, Asia and other parts of the world. We observed epidermal cells and syndetocheilic stomatal apparatuses, which corroborate an epidermal affinity to the Bennettitales. This new record would be the largest male reproductive structure found in the region thus far, and increases the distribution of Weltrichia in the Jurassic of Oaxaca.

Genetic analysis of Caenorhabditis elegans pry-1/Axin suppressors identifies genes involved in reproductive structure development, stress response, and aging

The Axin family of scaffolding proteins regulates a wide array of developmental and post-developmental processes in eukaryotes. Studies in the nematode, Caenorhabditis elegans, have shown that the Axin homolog, PRY-1, plays essential roles in multiple tissues. To understand the genetic network of pry-1, we focused on a set of genes that are differentially expressed in the pry-1-mutant transcriptome and are linked to reproductive structure development. Eight of the genes (ard-1, rpn-7, cpz-1, his-7, cdk-1, rnr-1, clsp-1, and spp-1), when knocked down by RNA interference, efficiently suppressed the plate-level multivulva phenotype of pry-1 mutants. In every case, other than clsp-1 and spp-1, the ectopic vulval precursor cell (VPC) induction was also inhibited. The suppressor genes are members of known gene families in eukaryotes and perform essential functions. Our genetic interaction experiments revealed that except for clsp-1, the genes participate in one or more pry-1-mediated biological events. While four of them (cpz-1, his-7, cdk-1, and rnr-1) function in VPC induction, stress response, and aging, the other three (spp-1, ard-1, and rpn-7) are specific to one or more of these processes. Further analysis of the genes involved in aging showed that his-7, cdk-1, and rnr-1 also interacted with daf-16/FOXO. The results of genetic epistasis experiments suggested that his-7 functions upstream of daf-16, whereas cdk-1and rnr-1 act downstream of the pry-1-daf-16 pathway. Altogether, these findings demonstrate the important role of pry-1 suppressors in C. elegans. Given that all of the genes described in this study are conserved, future investigations of their interactions with Axin and their functional specificity promises to uncover the genetic network of Axin under normal and disease states.

Monitoring environmental risk of the exotic species Kappaphycus alvarezii (Rhodophyta), after two decades of introduction in southeastern Brazil

Kappaphycus alvarezii was introduced for mariculture purposes on the coast of São Paulo, southeast of Brazil, in 1995, and since then an experimental pilot cultivation has been maintained. Since it is an exotic species, the dispersion of thallus fragments, presence of reproductive structures and recruitment from spores were monitored bimonthly from November 2016 to January 2018. Fragment dispersion was analyzed on nine selected monitoring sites around the cultivation raft through visual observation and photographic records. To verify the presence of reproductive structures 40 individuals were collected randomly from the cultivation raft and analyzed under a light microscope and stereomicroscope. Reproductive structure recruitment was also evaluated using artificial substrata. The results showed that even 25 years after the introduction of K. alvarezii on the coast of São Paulo, the invasive behavior of this exotic species had not been recorded. There was no evidence of vegetative dispersion and/or establishment in the Ubatuba Bay. Reproductive structures were also not found during the monitoring period. However, we highlight the importance of permanent and systematic environmental monitoring to prevent any impact and to ensure a sustainable aquaculture. These results will contribute to the development of the cultivation of the non-native K. alvarezii in Brazil and to improving public policies of coastal management.

Light and Electron Microscopic Studies of the Seminal Vesicular Glands of the African Straw-coloured Fruit Bat, Eidolon helvum

Background: Secretions from the seminal vesicular gland enhance the survival and reproductive functions of the spermatozoa. The order Chiroptera has evolved great diversity in their reproductive structure influenced by location, abiotic factors and availability of food. Eidolon helvum is a near threatened tropical African fruit bat and little is known of its reproductive biology. The aim of this study was to highlight the structure, histochemistry and ultrastructure of the seminal vesicular glands of Eidolon helvum. Methods: The paired seminal vesicular glands of 16 adult male Eidolon helvum were obtained in May during the early rainy season in tropical Nigeria. The glands were evaluated grossly, histological and ultrastructurally.Result: The spirally coiled tubular organs were divided into numerous lobules of tubular-alveolar glandular acini lined by simple cuboidal epithelium made up of basal cells and mono or bi-nucleated cuboidal secretory cells. PAS positive secretions projected from the apical surfaces. Principal secretory cells contained numerous rough endoplasmic reticulum, mitochondria, Golgi complexes, electron lucid secretory vesicles, electron dense granules and lysosomes. The unique merocrine and apocrine secretions contributed to the formation of vaginal plugs.

Physical characteristics of passionfruit cv. BRS gigante amarelo produced by flowers with three and four carpels

The carpel is the female reproductive structure composed of a set of stigma, style and ovary. Normally passionflower have three carpels, however, some cultivars have this structure in greater quantity. The objective of this work was to identify relationships between the number of carpels and the physical characteristics of BRS Gigante Amarelo fruits. The flowers with three and four carpels were marked, pollinated and the fruits harvested from these flowers analyzed for transverse diameter, longitudinal diameter, pericarp thickness, fruit mass, pulp mass, pulp ratio, number and weight of seeds. A completely randomized design with 10 replicates per treatment was used and each plot had the average of 3 fruits. The data were submitted to variance analysis and the means were compared by the Tukey test at 5% of probability. The fruits generated by flowers with 4 carpels were 18,30% heavier, their pulp were on average 20.75% heavier, presented transverse diameter 7,53% superior to that of fruits generated by flowers with 3 carpels. Similar increments were identified regarding the number of seeds and the weight of seeds per fruit that increased 18,85% and 52.42%, respectively. This result indicates that cv. BRS Yellow Giant with 4 carpels generates heavier fruits, pulp and seeds with a more spherical shape.