Night vision by cuttlefish enables changeable camouflage

SUMMARY Because visual predation occurs day and night, many predators must have good night vision. Prey therefore exhibit antipredator behaviours in very dim light. In the field, the giant Australian cuttlefish (Sepia apama) assumes camouflaged body patterns at night, each tailored to its immediate environment. However, the question of whether cuttlefish have the perceptual capability to change their camouflage at night (as they do in day) has not been addressed. In this study, we: (1) monitored the camouflage patterns of Sepia officinalis during the transition from daytime to night-time using a natural daylight cycle and (2) tested whether cuttlefish on a particular artificial substrate change their camouflage body patterns when the substrate is changed under dim light (down to starlight, 0.003 lux) in a controlled light field in a dark room setting. We found that cuttlefish camouflage patterns are indeed adaptable at night: animals responded to a change in their visual environment with the appropriate body pattern change. Whether to deceive their prey or predators, cuttlefish use their excellent night vision to perform adaptive camouflage in dim light.</jats:p

The burden of premature coronary heart disease among adults with low socioeconomic status in Argentina: A modeling study.

BackgroundThe well-established inverse relationship between socioeconomic status (SES) and risk of developing coronary heart disease (CHD) cannot be explained solely by differences in traditional risk factors.ObjectiveTo model the role SES plays in the burden of premature CHD in Argentina.Materials and methodsWe used the Cardiovascular Disease Policy Model-Argentina to project incident CHD events and mortality in low and high-SES Argentinean adults 35 to 64 years of age from 2015 to 2024. Using data from the 2018 National Risk Factor Survey, we defined low SES as not finishing high-school and/or reporting a household income in quintiles 1 or 2. We designed simulations to apportion CHD outcomes in low SES adults to: (1) differences in the prevalence of traditional risk factors between low and high SES adults; (2) nontraditional risk associated with low SES status; (3) preventable events if risk factors were improved to ideal levels; and (4) underlying age- and sex-based risk.Results56% of Argentina´s 35- to 64-year-old population has low SES. Both high and low SES groups have poor control of traditional risk factors. Compared with high SES population, low SES population had nearly 2-fold higher rates of incident CHD and CHD deaths per 10 000 person-years (incident CHD: men 80.8 [95%CI 76.6-84.9] vs 42.9 [95%CI 37.4-48.1], women 39.0 [95%CI 36.-41.2] vs 18.6 [95%CI 16.3-20.9]; CHD deaths: men 10.0 [95%CI 9.5-10.5] vs 6.0 [95%CI 5.6-6.4], women 3.2 [95%CI 3.0-3.4] vs 1.8 [95%CI 1.7-1.9]). Nontraditional low SES risk accounts for 73.5% and 70.4% of the event rate gap between SES levels for incident CHD and CHD mortality rates, respectively.DiscussionCHD prevention policies in Argentina should address contextual aspects linked to SES, such as access to education or healthcare, and should also aim to implement known clinical strategies to achieve better control of CHD risk factors in all socioeconomic levels

Regulation of epidermal growth factor receptor trafficking by lysine deacetylase HDAC6

Binding of epidermal growth factor (EGF) to its receptor leads to receptor dimerization, assembly of protein complexes, and activation of signaling networks that control key cellular responses. Despite their fundamental role in cell biology, little is known about protein complexes associated with the EGF receptor (EGFR) before growth factor stimulation. We used a modified membrane yeast two-hybrid system together with bioinformatics to identify 87 candidate proteins interacting with the ligand-unoccupied EGFR. Among them was histone deacetylase 6 (HDAC6), a cytoplasmic lysine deacetylase, which we found negatively regulated EGFR endocytosis and degradation by controlling the acetylation status of alpha-tubulin and, subsequently, receptor trafficking along microtubules. A negative feedback loop consisting of EGFR-mediated phosphorylation of HDAC6 Tyr(570) resulted in reduced deacetylase activity and increased acetylation of alpha-tubulin. This study illustrates the complexity of the EGFR-associated interactome and identifies protein acetylation as a previously unknown regulator of receptor endocytosis and degradation

Interactions between membrane-bound cellulose synthases involved in the synthesis of the secondary cell wall

AbstractIt has not yet been reported how the secondary CESA (cellulose synthase) proteins are organized in the rosette structure. A membrane-based yeast two-hybrid (MbYTH) approach was used to analyze the interactions between the CESA proteins involved in secondary cell wall synthesis of Arabidopsis and the findings were confirmed in planta by bimolecular fluorescence complementation (BiFC) assay. Results indicated that although all CESA proteins can interact with each other, only CESA4 is able to form homodimers. A model is proposed for the secondary rosette structure. The RING-motif proved not to be essential for the interaction between the CESA proteins.Structured summaryMINT-6951243: PIP2-1 (uniprotkb:P43286) physically interacts (MI:0218) with PIP2-1 (uniprotkb:P43286) by bimolecular fluorescence complementation (MI:0809)MINT-6950816: CESA4 (uniprotkb:Q84JA6) physically interacts (MI:0218) with CESA4 (uniprotkb:Q84JA6) by membrane bound complementation assay (MI:0230)MINT-6951056, MINT-6951071, MINT-6951088, MINT-6951103: CESA7 (uniprotkb:Q9SWW6) physically interacts (MI:0218) with CESA4 (uniprotkb:Q84JA6) by bimolecular fluorescence complementation (MI:0809)MINT-6950949, MINT-6950990: CESA4 (uniprotkb:Q84JA6) physically interacts (MI:0218) with CESA8 (uniprotkb:Q8LPK5) by membrane bound complementation assay (MI:0230)MINT-6950909, MINT-6951030: CESA4 (uniprotkb:Q8LPK5) physically interacts (MI:0218) with CESA7 (uniprotkb:Q9SWW6) by membrane bound complementation assay (MI:0230)MINT-6951042: CESA4 (uniprotkb:Q84JA6) physically interacts (MI:0218) with CESA4 (uniprotkb:Q84JA6) by bimolecular fluorescence complementation (MI:0809)MINT-6951004, MINT-6951016: CESA8 (uniprotkb:Q8LPK5) physically interacts (MI:0218) with CESA7 (uniprotkb:Q9SWW6) by membrane bound complementation assay (MI:0230)MINT-6951217, MINT-6951230: CESA4 (uniprotkb:Q84JA6) physically interacts (MI:0218) with CESA8 (uniprotkb:Q8LPK5) by bimolecular fluorescence complementation (MI:0809)MINT-6951120, MINT-6951140, MINT-6951156, MINT-6951170, MINT-6951185: CESA8 (uniprotkb:Q8LPK5) physically interacts (MI:0218) with CESA7 (uniprotkb:Q9SWW6) by bimolecular fluorescence complementation (MI:0809)MINT-6951199: CESA8 (uniprotkb:Q8LPK5) physically interacts (MI:0218) with CESA8 (uniprotkb:Q8LPK5) by bimolecular fluorescence complementation (MI:0809