Is life conceivable without chemotaxis Dr habil Khidai

Is life conceivable without chemotaxis ? Dr. habil. Kőhidai László 2011.

Trichinella spiralis (1) 200 - 400 + + 20 - 80

Trichinella (2) < + +

Trichinella (3) + + +

Insects (1) l Responses to pheromones: in sec. -s - direction of flying - speed - pattern (zick-zack) l Modulation of odorant receptors is durable 1 -2 min. - 20 -95 min. ipsenol, ipsdienol, cis-verbenol l Dose ranges of responses are wide

Insects (2) l Heat-dependent responses 20 o. C + steepness of flying 26 o. C l Different types of migrations/flying: schemakinezis tropotaxis klinotaxis zikk-zakk look-leap

Insects (3) l Cockroach pheromones inducing aggregation ammónia, methylamine, di-, trimethylamine 1 -dimethylamino-2 -methyl-2 -propanol effective in 10 p. M (50 -1000 x more active then other substances) l Differences in responses to diffuse and surface associated pheromones

Effect of gamones Coagulation Gynogamone II. Gynogamone I. Androgamone I. Hyaluronidase Androgamone II.

Parts of female sexual organs releasing chemoattractants l Cervical mucus l Cavity of uterus l Follicular fluide l Cumulus cells l Intact, still not fertilized oocyte

Components of follicular fluide Composition is sexual cycle dependant l LH l Progesterone (1 -100 mg/ml) l Adrenalin (0. 001 mg/mll l Oxytocin (0. 01 U/ml) l Insulin (repellens) l Kallikrein l Anti-thrombin III. = spermium receptor l Atrial natriuretic peptide (ANP=ANF) l 1000 Da, heat-stable protein l

Other factors synthesized by the female organs and influencing the chemotaxis l p. H l some proteases l resact – Ca 2+ [m. M] l speract – guanylate cyclase l chemoattractant substance perelased from the vegetative pole of oocyte Brown algae Ectocarpene 0. 89 – 8. 9 nmol/l the p-electone-distribution is essential

Spermiums and chemotaxis (1) l Population of spermiums is rather heterogeneous The respiratory response induced by follicular fluide: 70 % positive !!! 20 % negative l Responsiveness is changing by the age of cells: early matured aged only these cells express normal responsiveness

Spermiums and chemotaxis (2) Ca 2+ has a role in: chemotaxis cell respiratory proc. acrosome reaction cortocal reaction fertiléization cell adhesion Calmodulin – NAD-kinase – exocytosis phosphatases, phosphorylation guanylate cyclase c. GMP-depend. Ca 2+ channel Ca 2+ influx when spermium reaches the oocyte

Spermiums and chemotaxis (3) l Methylation system tail – protein carboxyl-methylase head – tail – MAP decreased phospholipid methylation (min. 40%) l c. AMP-dependent phosphorylation l Protein kinase inhibitors are blockers of the system (42 k. D kináz)

Spermiums and chemotaxis (4) l Common receptor-gene family in odorant receptors and in spermium l f. MLF and BOC-f. MLP (10 -9 – 10 -8 M) works as chemoattractant not only in leukocytes BUT in spermiums, too. (leukocyte accumulation is induced in the female genital tract) l p-nitrophenyl-glycerol (PNPG) 10 -5 M is repellent in spermiums – contraceptive applications

Characterization of pheromones Work on the individuals of the same species l Influence the sexual behaviour l Effects are expressed via pheromone-receptors l signaling is G-protein-linked l Influence development of hierarchy in the population qualitative differences quantitative l Excreted in: feaces, urine, sweet and other body-fluids l Determined by MHC-genes the same H 2 (male-female) prefer each other l

Pheromones (2) Mice Estrus-inhibition Anestrus Estrus (sensible period lasts 5 days, but mating desensibilizes it)

Pheromones (3) Non-self male excretes pheromones in the urine Level of heterozygocy is increased

Pheromones in lower levels of phylogeny (1) Saccharomyces cerevisiae 7 transmembrane receptor l G-protein-linked l Clathrin haevy-chain dependent internalization l Tetrahymena pyriformis l Attractant: tricosene ; imprinting + l Repellent: bornyl acetate ; imprinting 0

Pheromones in lower levels of phylogeny (2) l In Saccharomyces cerevisiae pheromones guide: - development of mating projections - intracellular migration of nucleus l Presence of N- and O-oligosaccharides a-agglutinin (cell adhesion) – in the core region 80 -95% O-oligosach. pheromones a-agglutinin-gene cell-cell contacts

Pheromones in lower levels of phylogeny (3) l Fungi – Allomyces macrogynus Sirenin (1 p. M – 1 m. M) l acts on gamets H+, K+, NH 4+, Na+, Ca 2+, Mg 2+, La 3+ - ions are repellent itself - they can neutralize effects of each-other in competition

Practical applications of pheromones l Artificial feritlization /insemination l Anti-helmintic l Insect repellent

„T-shirt” test Self – Non-self ? Male – Female ?

Pheromones in human (1) l Determination capacity of own-odor 75% l Distinguish male/female (female scores are better) l Newborns – recognition of lactating breast 2 days 2 weeks 6 weeks l Mating 0 + but no differentiation + mother preference

Pheromones Dog age (days) self non-self 20 -24 > 31 -36, 66 -72 ~ 52 -56 male

Pheromone in hide The chair labelled with male pheromone was preferred by female induviduals