Ultimate predators: lionfish have evolved to circumvent prey risk assessment abilities

Invasive species cause catastrophic alterations to communities worldwide by changing the trophic balance within ecosystems. Ever since their introduction in the mid 1980's common red lionfish, Pterois volitans, are having dramatic impacts on the Caribbean ecosystem by displacing native species and disrupting food webs. Introduced lionfish capture prey at extraordinary rates, altering the composition of benthic communities. Here we demonstrate that the extraordinary success of the introduced lionfish lies in its capacity to circumvent prey risk assessment abilities as it is virtually undetectable by prey species in its native range. While experienced prey damselfish, Chromis viridis, respond with typical antipredator behaviours when exposed to a common predatory rock cod (Cephalopholis microprion) they fail to visibly react to either the scent or visual presentation of the red lionfish, and responded only to the scent (not the visual cue) of a lionfish of a different genus, Dendrochirus zebra. Experienced prey also had much higher survival when exposed to the two non-invasive predators compared to P. volitans. The cryptic nature of the red lionfish has enabled it to be destructive as a predator and a highly successful invasive species

Glandular Trichomes on the Leaves of Nicotiana tabacum: Morphology, Developmental Ultrastructure, and Secondary Metabolites

Glandular trichomes found on the surface of many higher plants contain specialized cells that produce and secrete copious amounts of particular secretory products. Leaf glandular trichomes of the non-model plant species Nicotiana tabacum represent a biologically active and stress-responsive tissue that contributes to plant defense response against biotic and abiotic stress and also influences leaf aroma and smoke flavor. Two morphologically different types of tobacco capitate trichomes, long- and short-stalked, with distinct functions, display ultrastructural features that are common to terpene-secreting glands, but only the secretory cells of the tall glandular trichomes are considered to be the site of biosynthesis of certain exudate compounds, including diterpenes and sucrose esters. Ultrastructural and histochemical characterization of tall glandular trichomes is described in an attempt to understand the contribution of these glands to the total secretion produced. Possible roles of distinct cellular compartments involved in the secretory process and secondary metabolite secretion under in vitro conditions are discussed.Gopal RK, Ekiert HM, Goyal S, editors. Plant Cell and Tissue Differentiation and Secondary Metabolites. Springer, Cham; 2020. p. 1–37. (Reference Series in Phytochemistry)

Genome-wide association studies identify four ER negative-specific breast cancer risk loci

<p>Estrogen receptor (ER)-negative tumors represent 20-30% of all breast cancers, with a higher proportion occurring in younger women and women of African ancestry. The etiology and clinical behavior of ER-negative tumors are different from those of tumors expressing ER (ER positive), including differences in genetic predisposition. To identify susceptibility loci specific to ER-negative disease, we combined in a metaanalysis 3 genome-wide association studies of 4,193 ER-negative breast cancer cases and 35,194 controls with a series of 40 follow-up studies (6,514 cases and 41,455 controls), genotyped using a custom Illumina array, iCOGS, developed by the Collaborative Oncological Gene-environment Study (COGS). SNPs at four loci, 1q32.1 (MDM4, P= 2.1 x 10(-12) and LGR6, P = 1.4 x 10(-8)), 2p24.1 (P = 4.6 x 10(-8)) and 16q12.2 (FTO, P = 4.0 x 10(-8)), were associated with ER-negative but not ER-positive breast cancer (P> 0.05). These findings provide further evidence for distinct etiological pathways associated with invasive ER-positive and ER-negative breast cancers.</p>