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An effective conservation and management plan of Asian elephants in Peninsular Malaysia relies on understanding the population biology and ecology of the species. Since molecular genetic tools have been developed and widely used for elephant conservation, the Malaysian Department of Wildlife and National Parks (DWNP) aimed to obtain estimates of population size, individual identification and sex specific gene flow among elephant populations in Taman Negara National Parks (TNNP) in line with one of the long-term goals in the National Elephant Conservation Action Plan (NECAP). In this study, we apply non-invasive molecular techniques to sex Asian elephant faecal and we combine it with measurement of bolus dimensions to get reliable baseline information on sex ratio as well their age structure in TNNP, Peninsular Malaysia populations. Two Y chromosome specific fragments (SRY1 and AMELY2) and one X chromosome specific fragment (PLP1) were used to determine the sex of the elephants that were detected during our surveys in the TNNP study locations. A total of 217 fresh faecal samples from 31 sampling sites and measurements of each bolus circumference were analysed. Faecal samples from 10 elephant individuals of known sex from the National Elephant Conservation Centre (NECC), Kuala Gandah were included as controls. We identified 86 males and 131 females in TNNP via molecular sexing approach. In addition, to estimating the sex ratio in TNNP, we also categorized the different sexes into three different age classes by measuring mean of bolus circumference. Neonates/juveniles (Class 1) and sub-adults (Class 2) were composed of approximately an even number of males and females. However, our results of sexing, boli from adults (Class 3) revealed a lower number of males with 40 individuals compared to 84 females. This female biased sex ratio in adults could be due to poaching pressure on male adults around the study areas. Alternatively, we could have failed to detect more males because bulls are known to be more solitary and roam further in deeper forest areas away from their matriarchal herds and far from our sampling locations during our surveys. Despite these potential issues with detection of bulls, this study provided reliable information on the sex ratio pattern and age structure of free roaming elephant populations in TNNP. This information provides valuable scientific based management tools for DWNP as well policy makers in order to make decisions for future elephant conservation management plans in TNNP. [ABSTRACT FROM AUTHOR]

Stable cell-cell contacts underpin tissue architecture and organization. Quantification of junctions of mammalian epithelia requires laborious manual measurements that are a major roadblock for mechanistic studies. We designed Junction Mapper as an open access, semi-automated software that defines the status of adhesiveness via the simultaneous measurement of pre-defined parameters at cell-cell contacts. It identifies contacting interfaces and corners with minimal user input and quantifies length, area and intensity of junction markers. Its ability to measure fragmented junctions is unique. Importantly, junctions that considerably deviate from the contiguous staining and straight contact phenotype seen in epithelia are also successfully quantified (i.e. cardiomyocytes or endothelia). Distinct phenotypes of junction disruption can be clearly differentiated among various oncogenes, depletion of actin regulators or stimulation with other agents. Junction Mapper is thus a powerful, unbiased and highly applicable software for profiling cell-cell adhesion phenotypes and facilitate studies on junction dynamics in health and disease., Competing Interests: HB, CT, NM, PS, JE, SH, JG, SB, VB No competing interests declared, (© 2019, Brezovjakova et al.)

The class III phosphoinositide 3-kinase (PI3K) Vps34 (also known as PIK3C3 in mammals) produces phosphatidylinositol 3-phosphate [PI(3)P] on both early and late endosome membranes to control membrane dynamics. We used Vps34-deficient cells to delineate whether Vps34 has additional roles in endocytic trafficking. In Vps34 -/- mouse embryonic fibroblasts (MEFs), transferrin recycling and EEA1 membrane localization were unaffected despite elevated Rab5-GTP levels. Strikingly, a large increase in Rab7-GTP levels, an accumulation of enlarged late endosomes, and decreased EGFR degradation were observed in Vps34-deficient cells. The hyperactivation of Rab7 in Vps34-deficient cells stemmed from the failure to recruit the Rab7 GTPase-activating protein (GAP) Armus (also known as TBC1D2), which binds to PI(3)P, to late endosomes. Protein-lipid overlay and liposome-binding assays reveal that the putative pleckstrin homology (PH) domain in Armus can directly bind to PI(3)P. Elevated Rab7-GTP led to the failure of intraluminal vesicle (ILV) formation and lysosomal maturation. Rab7 silencing and Armus overexpression alleviated the vacuolization seen in Vps34-deficient cells. Taken together, these results demonstrate that Vps34 has a previously unknown role in regulating Rab7 activity and late endosomal trafficking., Competing Interests: The authors declare no competing or financial interests., (© 2016. Published by The Company of Biologists Ltd.)