Non-autonomy of AGAMOUS function in flower development: use of a Cre/loxP method for mosaic analysis in Arabidopsis

Angiosperms use a multi-layered meristem (typically L1, L2 and L3) to produce primordia that then develop into plant organs, A number of experiments show that communication between the cell layers is important for normal development. We examined whether the function of the flower developmental control gene AGAMOUS involves communication across these layers. We developed a mosaic strategy using the Cre/loxP site-specific recombinase system, and identified the sector structure for mosaics that produced mutant flowers. The major conclusions were that (1) AGAMOUS must be active in the L2 for staminoid and carpelloid tissues, (2) that AGAMOUS must be active in the L2 and the L3 for floral meristem determinacy, and (3) that epidermal cell identity can be communicated by the L2 to the L1 layer

Determination of audit activity in modern conditions

The task of compulsory audit of financial statements is the provision of reasonable assurance that is accepted and performed by the entity in accordance with the requirements of this Law and international standards of audit by checking the financial statements or consolidated financial statements in order to express an independent opinion of the auditor on its compliance with all significant aspects and compliance with the requirements of international financial reporting standards or national accounting (statutory) standards and laws of Ukraine

The neural network behind the eyes of a fly

With its regular, almost crystal-like structure, the fly optic lobe represents a particularly beautiful piece of nervous system, which consequently has attracted the attention of many researchers over the years. While the anatomy of the various cell types had been known from Golgi studies for long, their visual response properties could only recently be revealed thanks to the advent of cell-specific driver lines and genetically encoded indicators of neural activity. Furthermore, dense EM reconstruction of several columns of the fly optic lobe now provides information about the synaptic connections between the different cell types, and RNA sequencing sheds light on the transmitter systems and ionic conductances used for communication between them. Together with the molecular tools allowing for blocking and activating individual, genetically targeted cell types, the fly optic lobe can soon be one of the best-understood visual neuropils in neuroscience. In this review, we summarize what we have learned so far, and discuss the major difficulties that keep us from a complete understanding of visual processing in the fly optic lobe

In Healthy Subjects Nasal Nitric Oxide Does Not Correlate with Olfactory Sensitivity, Trigeminal Sensitivity, and Nasal Airflow

Objective: The aim of the study was to determine the relationship between nasal nitric oxide (nNO) and olfactory sensitivity, trigeminal sensitivity and nasal airflow in healthy subjects. Study design: This is a correlational study. Setting: This study was carried out in a tertiary referral centre. Participants: Forty healthy participants were recruited. Main outcome measures: nNO was measured using a chemiluminescence analyser (Niox Vero® , Circassia AB, Uppsala, Sweden), olfactory sensitivity was determined using phenyl ethyl alcohol odour thresholds using the 'Sniffin' Sticks', trigeminal sensitivity was assessed with carbon dioxide delivered by an automated device, and nasal airflow was measured using the peak nasal inspiratory flow (PNIF). Results: The median nNO was 518 ppb (IQR =333) in the right nostril, and it was 567 ppb (IQR = 314) in the left nostril. The median odour threshold was 7.1 (IQR = 4.4), the median CO2 threshold was 919 ms (IQR = 1297) and the mean PNIF was 108 L/min (SEM = 4.9). nNO did not correlate significantly with odour threshold, CO2 threshold or PNIF (Spearman's |ρ| .18). Conclusion: In healthy subjects, nNO does not appear to be associated with olfactory sensitivity, trigeminal sensitivity and PNIF.info:eu-repo/semantics/publishedVersio

A genetic and molecular model for flower development in Arabidopsis thaliana

Cells in developing organisms do not only differentiate, they differentiate in defined patterns. A striking example is the differentiation of flowers, which in most plant families consist of four types of organs: sepals, petals, stamens and carpels, each composed of characteristic cell types. In the families of flowering plants in which these organs occur, they are patterned with the sepals in the outermost whorl or whorls of the flower, with the petals next closest to the center, the stamens even closer to the center, and the carpels central. In each species of flowering plant the disposition and number (or range of numbers) of these organs is also specified, and the floral 'formula' is repeated in each of the flowers on each individual plant of the species. We do not know how cells in developing plants determine their position, and in response to this determination differentiate to the cell types appropriate for that position. While there have been a number of speculative proposals for the mechanism of organ specification in flowers (Goethe, 1790; Goebel, 1900; Heslop-Harrison, 1964; Green, 1988), recent genetic evidence is inconsistent with all of them, at least in the forms in which they were originally presented (Bowman et al. 1989; Meyerowitz et al. 1989). We describe here a preliminary model, based on experiments with Arabidopsis thaliana. The model is by and large consistent with existing evidence, and has predicted the results of a number of genetic and molecular experiments that have been recently performed