“I was quite a geeky teenager,” laughs Dr Clemens Kiecker, a senior lecturer, group leader at King’s College London’s Department for Developmen- tal Neurobiology, and winner of the Excellence in Teaching Award in 2014. “As a teenager I loved chemistry, but when I decided what I want to study, Chemistry seemed a bit too limiting at the time.” Clemens instead completed a Biochemistry degree at Freie Universitat Berlin: a welcome, forward-looking, and interesting challenge. Now, Clemens jokes that he has become “practically part of the furniture [at King’s,]” teaching anatomy, neuroscience, and embryology while waiting for a journal to hear about a recently submitted paper. Before moving to London in 2001, Clemens grew up in Berlin, where he completed his undergraduate diploma before pursuing a PhD in biology at Heidelberg University. “I just saw a poster, an advertisement, for a PhD position in Heidelberg,” Clemens remembers, “and it turned out that the guy who advertised it had studied Biochemistry in Berlin, done a PhD in Heidelberg and a postdoc in the US and came back and has started his own lab.” This was Professor Christof Niehrs, who has since become a Founding, Scientific, and Executive director of the Institute of Molecular Biology in Mainz, Germany. Clemens had flipped through scientific magazines and realized that “the nineties were a very good time for Developmental Biology:” the scientific community was boasting discoveries of organizers and regulatory factors allowing the formation of an organism based on its genetic instructions.
In 1997, the Niehrs group had recently published a paper detailing the discovery of a new gene called dickkopf1, or dkk1, “which I know sounds rather rude,” Clemens interjects, “but in German it just means stubborn or big-headed.” At the start of his PhD, the new dkk1 gene was relatively poorly understood beyond its classification as a wnt inhibitor. Knowing that he wanted to pursue a career in academia and research, Clemens sees his choice to do his PhD in the Niehrs lab as “a mix of opportunity and genuine interest.” The first part of Clemens’ PhD, trying to identify potential effectors of the dkk1 gene, didn’t yield many results, prompting him to get “a little side- tracked” and venture into the realm of biochemistry. “To make a long story short,” Clemens says, “in the first year of my PhD nothing really worked, and I think that’s very typical… Very often you have long periods of drought, it’s very rare in science that a project works all the time, and often you need to try and try again.” As he was doing work with dkk1, though, he “stumbled across another gene,” also recently published and with very little knowledge on the mechanisms involved. Clemens switched gears and began injecting embryos with this new gene, which was naturally very exciting until, half a year later, a group announced that they had found exactly what he’d been working on.
“I was really distressed and unhappy about it, and frustrated,” Clemens reflects, “so then the question was basically ‘What now?’” In the Niehrs lab, it appeared as though everyone was working on the dkk1 gene, leading Clemens to find something “that would be [his] own project.” Thus, instead of pursuing dkk1 and its role in promoting anterior (and head) development in a growing embryo, “which there is this underlying idea that anterior development happens by default,” Clemens endeavoured to understand the promotion of posterior (trunk/tail) development. The hypothesis was that the relationship between the posterior signals and the anterior signals is an antagonizing one, allowing the body axis, head to tail, to develop. “We took this one further,” Clemens explains, building upon a 1950s study establishing a posterior-to-anterior signalling gradient and focusing on the central nervous system (which encompasses the brain and spinal cord), largely due to the ease with which the prospective forebrain, midbrain, hindbrain, and spinal cord could be visualised using genetic markers. “At that point things started to work really well,” Clemens says. “There’s no guarantee, of course, that things will start to work, but you need to be tenacious to some extent to get there.” He published his PhD thesis in early 2001, followed by a couple of review articles and book chapters, which was “really fun.” This experience prompted his ultimate interest in central nervous system development and he found a post-doctoral position at King’s College London with Professor Andrew Lumsden, founder of the MRC Centre for Developmental Neurobiology at King’s. He had lunch with Andrew Lumsden to talk about the job, and had moved to London by December 2001. This was “daunting and exciting at the same time,” he explains. He was able to move into an accommodation with friends and “basically fell into a made nest, so to say.”
The only true difficulty, Clemens explains, was setting up phone numbers and bank accounts. “I thought, I’m German, normally Germans have, like, this reputation for being really bureaucratic,” he laughs, “but I found that the British can be really quite bureaucratic.” Regardless, Clemens found himself in an extremely welcoming environment; colleagues took him to lunch and parties and helped smooth his transition into the workplace at King’s, “and there was this international capacity of developmental biology showing me how to dissect chicken embryos.” By 2010, Clemens was offered a lectureship at King’s, which he felt was the natural next step for him in his career while also allowing him to stay in London, “which by that point felt like it was essential.” “I felt like since I’d moved,” Clemens reflects, “not that I’d had a horrible time before, but since I’d moved to London that was kind of the best time of my life.” By that point, London had grown to represent “a network of friends, I’ve got a house here now, my partner is English… at some point you want to put your roots down somewhere.” Clemens now “enjoys the luxury” of being able to be involved both in education and in conducting research. As someone who enjoys teaching, he finds that that part of his work somewhat eases the pressures of having to constantly secure research funding. Just like the rest of society, the major funding bodies have been affected by the global financial crisis in 2008, making the research funding situation more competitive. However, Clemens is reassuring that pursuing a passion in the basic sciences is entirely possible, as nearly half of Research Council funding is dedicated to Medical, Biological, and Biotechnological Sciences. Beyond a career in research, Clemens enjoys making his impact on society by helping to educate the “scientists and doctors of tomorrow:… obviously science is very important – but you work on a very, very specific, minute piece of the puzzle,” he explains. By leaning into education, “I’m also capitalizing on what my strengths are.” Now, in collaboration with a group of researchers at King’s, Clemens has discovered a new placode, a specialised structure of the embryo that contributes to components of the sensory nervous and neuroendocrine system.
Clemens continues to search for further under- standing in the field of embryology and neuroanatomy, reflecting that he has “never been driven much
by the need to develop a cure for a disease… It was much more like… the same reason as to why astrophysicists use strong telescopes to look into space. It’s more about there being a phenomenon, and I want to understand it.”
some more science:

Prof Niehrs & dkk1

dkk1, dickkhopf-1, is a Wnt-signalling inhibitor crucial for the regulation of anterior-posterior patterning, eye formation, limb development, and other processes fundamental to a vertebrate’s development. Wnt is essential for embryonic patterning: fore- brain formation requires Wnt inhibition, while conversely, Wnt must be present to form the spinal cord. Thus, injecting dkk1 into Xenopus embryos inhibits Wnt signalling and yeilds frogs with bigger heads and shorter trunks and tails. dkk1 antagonizes the Wnt/β-catenin pathway by reducing β-catenin, a protein essential for embryonic patterning and stem cell renewal, as well as a morphogen in epithelial cells. Dr Clemens Kiecker’s question was the following: do Wnt signals function as morphogens to regulate the head-to-tail axis in a dose-dependent fashion? In other words, he was looking to understand whether progressively more Wnt present posteriorly in the embryo will result in the formation of progressively posterior central nervous system structures (forebrain, midbrain, hindbrain, and spinal cord). It was ultimately found that, indeed, a gradient of Wnt/β-catenin signalling is responsible and essential for the patterning the frog’s central nervous system.

Prof Lumsden and ZLI signaling:

During embryonic development, neurulation, the process of transforming the neural plate into the neural tube, is known to feature two main organizing centers, dictating the boundaries between the brain regions.
The Midbrain-Hindbrain Boundary (MHB) or isthmic organizer functions as its name implies, and the anterior neural boundary/ridge (ANR) is essential for the formation of the forebrain. The MHB relies on FGF8 and Wnt1 to induce formation of the midbrain, cerebellum, and hind- brain, while the ANR expresses Emx1 and dlx to establish forebrain positional identity. The Zona Limitans Intrathalamica (ZLI), a wedge of cells in the diencephalon, was shown by Lumsden and Kiecker to rely on Shh (Sonic hedgehog, a morphogenic protein) signalling for both the growth and regional identity of the diencephalon. In fact, the thalamus and prethalamus, located on either side of the ZLI, demonstrate differential responses to Shh signaling, and that thalamic differ- entiation is a sequential process, where Wnt signaling pre-patterns the diencephalon before ZLI Shh expression induces its development.

Dr Kiecker and the pineal placode

Previously, the pineal gland, involved in circadian rhythms, was thought to be derived from the neural plate, a central nervous system predecessor. Current work at KCL has found evidence that the pineal gland is also arising from the adjacent non-neural ectoderm which typically develops into placodes. It follows that the group have uncovered a new, pineal placode.
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