Gardner: Placental genotype affects pre/early postpartum maternal behavior in an interspecific cross

all right great so hello I'm Sarah Gardner I'm a graduate student at UC Riverside but I am unit our team elsewhere my Master's work that really got the publication this morning all right okay so but a lot of these behaviors really impact offspring phenotype so things like early survival down to their overall fitness and in Rodin's in particular levels of maternal behavior have been shown to impact offspring behavioral phenotypes so for example the female provides less care to her offspring those offspring in turn show increased anxiety like phenotypes and as well are not as a good parents to their own offspring so I think it's safe to say we know a fair amount about how mothers can impact their offspring but maybe with less talk about is how offspring can turn around and impact their mothers so at least in mammals these interactions are mediated through the placenta so I'm going to give you a quick crash course on what you need to know about myself so placenta are of offspring origins so we mean by that other than a really later a paternal tissue that Sesenta same genotype as developing embryo and also the placenta acts as a temporary endocrine organ so it's producing hormones that target the maternal brain that trigger a change in her physiology her metabolism and even her behaviors an importantly a subgroup of these hormones and rodents called the central oxygen target the maternal brain to frighten her to be ready to act internal the second those pups are born bringing back to being reciprocal her offspring received really big benefit for her being ready to act maternal once her pups their corn and then lastly imprinted genes are highly expressed in the sentence so imprinted genes are apparent of origin specific so only either the paternally inherited allele worth of maternally inherited we are expressed for a given gene brings imprinted genes when said they're highly expressed in the placenta and in particular in the placental and results so those cells that are producing those hormones that trigger all these cascading things that leaves this great offspring benefit so that leads me to our study species so in our lab we use crosses set up between muscular this to the house mouse and mouse press Algeria most animal hybrids that show missed expression of imprinted genes in Ascenta and also in the hybrid so in particular others in my lab have looked at what genes are missed expressed in these editor percenter and to that I'm going to point out in particular filled in to you and ask Allah to are expressed in the inner compartment and then note that I didn't say about these hybrids is that in the direction of the Prophet we're looking at the hybrids are under sized and so also the septa is under sized and also the entry compartment is under sized and then not imprinted genes but still important the simple nitrogens are also missed expressed in hydro Senta and they're under expressed so all this together is preached drama of interest some sort of placental dysregulation happening in this price so that brings me to a question do females that are exposed to this Hydra cinta did for maternal behaviour compared to the females that we have seen conspecific offspring and based on the fact of all these evident of all of the evidence that we've seen that there's placental dysregulation in this cross they expect to see that there is some sort of altered maternal care in the females using magnets compared to those for PC and to do this we set up two experimental crosses domesticus females denoted as Dom here we're either parent to a male domesticus and a specific offspring or they repaired to male spreads to go to spread up here and reduce Tigers so regardless what kind of offspring they were producing we subjected them to where people test before they gave birth we wanted to see if there was an increased anxiety phenotype in the mothers so we put them through an open field test and then after the books are born they participated in poetry will test shuffling and they'll cut it down to see how much milk the females are producing and how much their thoughts pretty and lastly daily time in and out the nest using an activity monitor placed on top of the cage and these were done pepper tingles done on the first day the pups were born suckling a milk bath on steam on day five after the reward and do time that's what's done over the first four days postpartum so when maternal behaviors are usually at their highest all right so I'm gonna present the data for these probably so from pregnancy and postpartum and for all the graphs that you're gonna see any of the data with hybrids have certain mothers of hybrids art blue and red for compensation so first up is the open field test and I'm only showing you two metrics we measured for this time Center and we enter the center of the arena so these are just open grids that place the female 10th to see if they show aging society like the majors so my surprise he sees if they're out in the open have a pretty good chance of something coming along unit so they typically try to stay around these outer edges if this in this open space so an increased or decreased anxiety length behavior would be spending more time in the nest and getting their very promise in a central part and getting in there faster okay so first for timing Annette Center as females of pregnant with hybrid offspring are getting closer to partition they're spending more time in this mr. Mina which is indicative of less anxiety on behavior but conversely for ladies easy to enter the center they're pretty static as a being posted apart Rishon but are still consistently higher so they're maybe they're taking longer to enter into the center of the arena but they're spending more time there since a bit of a mixed bag all right and then once the cops are involved so if I retrieval just real fast is exactly what it sounds like I took three puffs and took them out of the nest and then we see how it took for moms to retrieve them so for all of their pups mothers of hiding offspring took longer to retrieve okay so next up its homepage activity so we use activity kinds of proxy for time and amount of the nest because they're more active outside of anezka monitors people got up so they're out of the nest then but decreased activity is indicative of more time nest so we found was that on this first night oh also Emily joining dark cycle activity because mice are eternal and so they're more active in the dark cycle anyway but mothers are kind of expected to not be as active they're spending time spending time with us and so on this first night we see that mothers of hybrid offspring are actually more active or spending more time out of the nest compared to others the process of offspring but this goes with creating with the abductors thing all right and lastly is the suckling reflect down assets so for each of these six time points we wait each mother and then all their puffs individually so what this test is doing we take the pups out of the nest for two hours to see how much milk another is producing and then put them back in the nest and then see how much eight over four hours all right so I'm going to show you mother and cup data separately first off mother's it's two lines noticing they did not different between the two girs they're gaining weight when they're separated from their cuffs and difficulties they're losing weight the pups were not also that different other than at this one time point so it looks like hybrid pups are actually losing last week their births all right so just in summary actually the question do females exposed to have incentive differ in maternal behaviors compared to be responsive a off-screen yes we have some open infant up is the case but more specifically going back through what we're looking at did they show increased anxiety length behaviors prepartum yes you know they're a bit contradictory but I think the important point here with even they are different the females that are pregnant with hybrids are acting differently than the females that article our campaign promises a big offspring but we did see longer latency to your tree pups and less time spent in the nest on the first night so both of these metrics were taken on the first day of the Pope's born which is really really critical to their survival that they're not spending too much time out of the nest so they can't thermoregulate so the longer that they're outside of the nest they're increasing your risk of hypothermia and again we need a predator across them in and seeing time spent out of the nest that mothers aren't there to keep warm so what do we think this means um I'll remind you that we do have a lot of evidence for the central dysregulation during pregnancy so this presented dysregulation is probably leading to altered signaling that Prime's those returning the haters so this altered table and probably leads to these early return invaders kind of deficits and earlier terminators but constant exposure to those pups over the first couple of days really removes that effect so by day five others were more or less become sensitized bear cubs and even inversion growing rodents that in constantly exposing email puffs eventually shall start acting maternal so these females are still getting some hormones however like I was mentioning before beginning any sort of deficit can still really impact offspring in the long run so despite the fact that this fact goes away eventually the fact that early times was not as great at the to the bed basically this can still have a long-term impact on house printed and also the future meets a little bit earlier at the direct mechanism while the gentle Africans are under expressed to see great with that I just want to thank my many of them yeah it's like jingling director right and so I would have mentioned that a smaller being with drink less milk right yes and over litter sizes too because I mean they were buried between both groups but right I really want to look at that but unfortunately with this strain of WSB that we have they wouldn't do the other direction of the cross but yes they are oversized thank you

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