My transcriptome will go on…

The blog entry of today might seem a bit esoteric dealing with the question whether there is scientific evidence for a life after death. According to recent findings in the field of genomics there is – at least a kind of. Researchers reported that some genes become actively switched on after an organism deceased, the so-called thanatotranscriptome. In their study, researchsers investigated active gene transcription in mice and fish after a postmortem period of 6 minutes up to 4 days.

Firstly, they found that beeing dead is quite stressful. Rest in piece – as if! Many genes of the stress response and cellular transport are triggered in order to fight the progressing biochemical mess and the loss of control over the putrescent body. A quite hopeless waste of remaining energy…
Secondly, being dead is similar to being ill. I guess, all the males will now feel confirmed with their I-have-a-flu-I’m-dying  attitude. Genes involved in the immune and  inflammatory response become switched on after death inducing a fight against proliferating bacteria and progressing cellular damage. Thridly, death induces death. How logical science is, right? Apoptotic mechanisms are kicked off in order to eliminate cells which are not viable anymore. Spoiler alert: that will be quite some!

So far, all of the above findings have been relatively predicatable. But another observation of this study was less straight forward to believe: Death induces life. At least in a broader sense. Some developmental genes, which are usually highly controled and most carefully orchestrated during embryogenesis, become switched on after death. These genes are involved in the formation of certain structures within the developing embryo and it is unclear why they become reactivated after having been silenced meticulously. The autors of the article ascripted this to the biochemical mess, which could be similar in development and decay.

How do these findings influence our perception of life and death? There is a rational point of view: biological processes go on automatically until cells are running out of energy and the battery is empty. Gene transcription is  epigentically controled by biochemical stimuli of the environment and after death, cells just use the remaining energy and react on the surrounding disorganisation. By this, the body automatically fights the consequences of death. Coincidentally, these environmental changes resemble the embryonic milieu and developmental genes become switched on…

A more esoteric point of view – and I do not state that this is my personal opinion – could be that the deceased body is preparing for rebirth. Many cultures and religions believe in rebirth or in a life on another level, like heaven. I personally like these ideas because it has something consolatory and it changes the perception of death. Could the genetic fight against death and the reactivation of developmental genes mark a transitory phase between the ending life and the next, soon beginning life?

The lab animals used in this study did not die because of age or disease, their bodies still had a lot of “rest energy” when they were killed. It would be interesting to see if the thanaotranscriptome of naturally deceased organisms is different from that who were actively killed. This study is clearly under debate but as long as no one proves us wrong, we can feel free to interpret these results in the way we wish…

XOXO, your Nerd

 

Let’s talk about snails

Zoology is the reason why I studied biology. I am fascinated by animals, their behaviour, their adaptations, and their „special features“. Unfortunately, the first thing you get to learn when you start to study zoology is that it will be hard to find a job later on. Eventhough, I chose genetics and pharma as my main subjects, zoology has still a place in my heart and so I would like to share some oddities of the animal kingdom with you.

The exciting sex life of snails

IMG_2290 aTodays issue is about the snail, a completely underestimated and overseen animal. But actually, these guys are pretty cool! I am housing 15 achat snails (Achatina fulica) and I don’t get tired of Snail-Watching. Snails are social animals and love beeing in a crowd but most likely you will encounter them alone when they are ‘on the road’. Snails love to cuddle and the smaller ones like to have a piggyback ride on the bigger ones. But the really interesting thing about snails is their secret but extravagant sex life. They are not prude and some species love to do it in a group with their flirtation taking up to 12 hours. Whenever they are not hungry or sleepy they make love…

Terrestrian snails are hermaphrodites, which means that each individual has male and female sexual organs (the absence of a conflict of sexes might explain their mutual consent about certain sex practices…). Mating strategies vary among different species but here a two virtuous exaples:

The first example comes from the grapevine snail (Helix pomatia). In their foreplay, these snails make use a sadomassnails-love-darto practice and shoot, cupido-like, a love-dart into the body of their partner. These darts are up to one centimeter long and consist mainly of calcium carbonate. The darts are coated with a stimulant, which increases the peristaltis in sperm-transporting tubes to increases the chances for paternity. The image does neither show the grapevie snail, I guess it’s Helix aspersa Mueller, nor is it biologically correct but it really makes me smile 😉

220px-Limax-maximus_mating_2The second example comes from the leopard slug (Limax maximus). This guy does not only look super stylish with its leopard print, it also has an unusual mating method which could be a performance in Cirque du Soleil! When two of these hermaphordites meet, they start licking each others tail tip so that they are crawling in a circle for a while. When they are stimulated enough, they produce a long thread of mucus and hang suspended in the air from a tree branch, drip rail or other. Swinging upside-down in this position, called lamp globe, they mate. Image by wikipedia.

Worth mentioning that a mating of these hermaphrodites usually results in the mutual exchange of sperm so that both partners can become „pregnant“- But they can decide when the time is right to fertilize the eggs by their own sperm bank! Snails can store sperm up to two years until they feel that the time is right to have their babies.

I hope, I could convince you that snails are worth a closer investigation,

XOXO, your Nerd