TY - JOUR TI - Acquisition of exogenous haem is essential for tick reproduction AU - Perner, Jan AU - Sobotka, Roman AU - Sima, Radek AU - Konvickova, Jitka AU - Sojka, Daniel AU - Oliveira, Pedro Lagerblad de AU - Hajdusek, Ondrej AU - Kopacek, Petr A2 - Pal, Utpal VL - 5 PY - 2016 DA - 2016/03/07 SP - e12318 C1 - eLife 2016;5:e12318 DO - 10.7554/eLife.12318 UR - https://doi.org/10.7554/eLife.12318 AB - Haem and iron homeostasis in most eukaryotic cells is based on a balanced flux between haem biosynthesis and haem oxygenase-mediated degradation. Unlike most eukaryotes, ticks possess an incomplete haem biosynthetic pathway and, together with other (non-haematophagous) mites, lack a gene encoding haem oxygenase. We demonstrated, by membrane feeding, that ticks do not acquire bioavailable iron from haemoglobin-derived haem. However, ticks require dietary haemoglobin as an exogenous source of haem since, feeding with haemoglobin-depleted serum led to aborted embryogenesis. Supplementation of serum with haemoglobin fully restored egg fertility. Surprisingly, haemoglobin could be completely substituted by serum proteins for the provision of amino-acids in vitellogenesis. Acquired haem is distributed by haemolymph carrier protein(s) and sequestered by vitellins in the developing oocytes. This work extends, substantially, current knowledge of haem auxotrophy in ticks and underscores the importance of haem and iron metabolism as rational targets for anti-tick interventions. KW - haem auxotrophy KW - haem oxygenase KW - iron metabolism KW - haematophagy JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -