Evolution of egg size and fertilisation efficiency in sea stars: large eggs are not fertilised more readily than small eggs in Patiriella (Echinodermata: Asteroidea)

Fertilisation kinetics theory suggests that, when sperm are limiting, the larger eggs of broadcast-spawning marine organisms ought to be fertilised more frequently than smaller eggs, because they provide a bigger target for searching sperm. Whilst this effect has been demonstrated within species, it is not known if this pattern holds among species. We tested whether a large difference in egg size between congeneric seastars with contrasting planktotrophic and lecithotrophic modes of development results in differences in the likelihood of eggs being fertilised in sperm-limiting situations. Measurement of egg sizes and sperm swimming speeds led to the prediction that the sperm–egg collision rate constant for Patiriella calcar (420-µm-diameter egg) should be nine times greater than for P. regularis (140-µm-diameter egg). Although the eggs of P. calcar should be fertilised at greater rates in low sperm concentrations, they were not. When gametes were allowed to mix for 10 s, the hypothesis that P. calcar eggs required less sperm than P. regularis to ensure 50% of eggs were fertilised was rejected. When gametes were mixed for 5 min, P. regularis eggs were more frequently fertilised, but the difference was not statistically significant. We conclude there must be a difference between these species in the likelihood that when a sperm finds a conspecific egg it can successfully fertilise. This apparent uncoupling of egg size and likelihood of fertilisation suggests that fertilisation is not a major constraint on the evolution of egg size in these seastars.

Regulation of STARS and its downstream target suggest a novel pathway involved in human skeletal hypertrophy and atrophy

Skeletal muscle atrophy is a severe consequence of ageing, neurological disorders and chronic disease. Identifying the intracellular signalling pathways controlling changes in skeletal muscle size and function is vital for the future development of potential therapeutic interventions. Striated activator of Rho signalling (STARS), an actin-binding protein, has been implicated in rodent cardiac hypertrophy; however its role in human skeletal muscle has not been determined. This study aimed to establish if STARS, as well as its downstream signalling targets, RhoA, myocardin-related transcription factors A and B (MRTF-A/B) and serum response factor (SRF), were increased and decreased respectively, in human quadriceps muscle biopsies taken after 8 weeks of both hypertrophy-stimulating resistance training and atrophy-stimulating de-training. The mRNA levels of the SRF target genes involved in muscle structure, function and growth, such as α-actin, myosin heavy chain IIa (MHCIIa) and insulin-like growth factor-1 (IGF-1), were also measured. Following resistance training, STARS, MRTF-A, MRTF-B, SRF, α-actin, MHCIIa and IGF-1 mRNA, as well as RhoA and nuclear SRF protein levels were all significantly increased by between 1.25- and 3.6-fold. Following the de-training period all measured targets, except for RhoA, which remained elevated, returned to base-line. Our results show that the STARS signalling pathway is responsive to changes in skeletal muscle loading and appears to play a role in both human skeletal muscle hypertrophy and atrophy.

Evaluating New Zealand sports stars as celebrity endorsers : intriguing results

Celebrity athlete endorsement of products and services has become prominent in the promotional mixes of New Zealand companies and organisations. For years advertisers and researchers have pondered how successful celebrity athlete endorsement really works. Most suggest some form of transfer of positive images takes place between celebrity and the product or service they are endorsing and source-credibility models have become the preferred research design. The overall objective of this research was to assist sport marketing managers and their advertising agencies in matching celebrities with products and services. An ancillary objective was to compare results obtained from multiple-item and single-item scales. An exploratory study with tertiary students was conducted, using both Ohanian’s (1990) 15 item source-credibility scale and two single-item measures to examine potential “endorsement fit” for four New Zealand sporting heroes. They were Bernice Mene (recently retired national netball team captain), Dean Barker (America’s Cup yachting defender’s helmsman), Mandy Smith (recently retired national women’s hockey team star) and Justin Marshall (All Black rugby’s most capped halfback), all of whom were adjudged by students as physically attractive sports stars. The product reported here against which these athletes were scored was an isotonic sports drink. Results were mixed; the Ohanian source-credibility scale yielded selection of different celebrity athletes to the single-item measures. The research results show that matching celebrities to products for potential endorsement opportunities is a complex issue, leaving scope for judgement and intuition alongside quantification. Still unresolved is the question of multiple-item measures versus single-item measures in advertising and service research.

Striated muscle activator of Rho signalling (STARS) is a PGC-1α/oestrogen-related receptor-α target gene and is upregulated in human skeletal muscle after endurance exercise

Exercise improves the ability of skeletal muscle to metabolise fats and sugars. For these improvements to occur the muscle detects a signal caused by exercise, resulting in changes in genes and proteins that control metabolism. We show that endurance exercise increases the amount of a protein called striated muscle activator of Rho signalling (STARS) as well as several other proteins influenced by STARS.We also show that the amount of STARS can be increased by signals directed from proteins called peroxisome proliferator-activated receptor gamma co-activator 1-α (PGC-1α) and oestrogen-related receptor-α (ERRα). We also observed that when we reduce the amount of STARS in muscle cells, we block the ability of PGC-1α/ERRα to increase a gene called carnitine palmitoyltransferase-1β (CPT-1β), which is important for fat metabolism. Our study has shown that the STARS pathway is regulated by endurance exercise. STARS may also play a role in fat metabolism in muscle.

Seasonal winds drive water temperature cycle and migration patterns of Southern Australian giant crab Pseudocarcinus gigas

The giant crab Pseudocarcinus gigas occurs along the continental shelf break of southern Australia. During the summer alongshore winds cause cooler water to upwell onto the shelf, and the crabs move from deeper water onto the shelf where there is more food. The combination of a preferred thermal niche and a depth-stratified food supply defines the favorable foraging environments that enhance the growth of P. gigas. Climate change is expected to cause a southerly shift of the austral subtropical high-pressure belt, and modelers have predicted more upwelling-favorable winds. The associated increase in the circulation of cooler water across the shelf is likely to provide P. gigas with an increased access to benthic food resources and their growth rate may increase in some regions.

Wings or winds : inferring bat migration in a stepping-stone archipelago

Eocene ocean currents and prevailing winds correlate with over-water dispersals of terrestrial mammals from Africa to Madagascar. Since the Early Miocene (about 23 Ma), these currents flowed in the reverse direction, from the Indian Ocean towards Africa. The Comoro Islands are equidistant between Africa and Madagascar and support an endemic land vertebrate fauna that shares recent ancestry predominantly with Madagascar. We examined whether gene flow in two Miniopterus bat species endemic to the Comoros and Madagascar correlates with the direction of current winds, using uni- and bi-parentally inherited markers with different evolutionary rates. Coalescence-based analyses of mitochondrial matrilines support a Pleistocene (approximately 180 000 years ago) colonization event from Madagascar west to the Comoros (distance: 300 km) in the predicted direction. However, nuclear microsatellites show that more recent gene flow is restricted to a few individuals flying against the wind, from Grande Comore to Anjouan (distance: 80 km).

The regulation and function of the striated muscle activator of rho signaling (STARS) protein

Healthy living throughout the lifespan requires continual growth and repair of cardiac, smooth, and skeletal muscle. To effectively maintain these processes muscle cells detect extracellular stress signals and efficiently transmit them to activate appropriate intracellular transcriptional programs. The striated muscle activator of Rho signaling (STARS) protein, also known as Myocyte Stress-1 (MS1) protein and Actin-binding Rho-activating protein (ABRA) is highly enriched in cardiac, skeletal, and smooth muscle. STARS binds actin, co-localizes to the sarcomere and is able to stabilize the actin cytoskeleton. By regulating actin polymerization, STARS also controls an intracellular signaling cascade that stimulates the serum response factor (SRF) transcriptional pathway; a pathway controlling genes involved in muscle cell proliferation, differentiation, and growth. Understanding the activation, transcriptional control and biological roles of STARS in cardiac, smooth, and skeletal muscle, will improve our understanding of physiological and pathophysiological muscle development and function.

Winds of change in Myanmar? Implications for international cooperation In poverty alleviation

We are witnessing the beginnings of what could well be significant change in Myanmar. Elections in November 2010 were quickly followed by the release of opposition leader Aung San Suu Kyi, then by the resignation of Senior-General Than Shwe, dissolution of the State Peace and Development Council (SPDC), the opening of parliament, and the inauguration of Thein Sein as President on 30th March 2011. Thein Sein's inauguration speech called for national reconciliation and an end to corruption, promised a more market-oriented economy, and vowed to create employment opportunities. He also pledged to develop the health and education sectors in cooperation with international organisations, and to alleviate poverty. While some fear this may only be rhetoric, a growing number of indications suggest that major political and economic reform may indeed be getting underway. This paper traces these recent developments and the possibility of significantly improved international development cooperation in Myanmar, particularly as it affects the prospects of poverty alleviation efforts and cooperation with Western INGO and multilateral agencies. It analyses the implications of this reform on international development assistance and cooperation from the perspectives of humanitarian needs, international relations theory, development theory, and political philosophy.

Review short: Rebecca Law's Lilies and Stars

Review of Lilies and Stars by Rebecca Law, Picaro Press, 2013.

The role and regulation of stars in skeletal muscle

STARS is a muscle specific protein that is upregulated in response to endurance exercise and may potentially increase skeletal muscle cell sensitivity to muscle contraction. STARS enhances the activation of intracellular signalling pathways involved in skeletal muscle growth, regeneration and oxidative metabolism.