First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Stefanie Jennnifer Oeding is the first author on ‘Identification of Miro1 and Miro2 as mitochondrial receptors for myosin XIX’, published in Journal of Cell Science. Stephanie was a PhD student in the lab of Professor Martin Bähler at University of Münster, Germany, and is currently working in cell line development at Rentschler Biopharma in Laupheim, Germany.

Stefanie Jennifer Oeding

How would you explain the main findings of your paper in lay terms?

We know that mitochondria are the powerhouses of eukaryotic cells. However, it is important that these powerhouses are located where they are needed within cells, for example, at sites where local energy demand is high. Mitochondria are transported by motor proteins, which can bind to and move along molecular tracks formed by either microtubules or actin filaments. One of these motor proteins is myosin 19, which specifically binds to actin filaments. We could show that myosin 19 binds to mitochondria via a linker protein called Miro, which is extremely interesting because Miro is also known to link microtubule-based motor proteins to mitochondria. Thus, our findings indicate that Miro plays a pivotal role in mitochondrial transport by linking both microtubule- and actin-based motor proteins to their respective molecular tracks.

Were there any specific challenges associated with this project? If so, how did you overcome them?

What it really means [to be scooped] … can really only be appreciated when it happens to you.”

As a young scientist, every now and then you hear that labs get ‘scooped’. But what it really means, and how devastating it can be to see your findings published by another lab, can really only be appreciated when it happens to you. And we got scooped. All my motivation was gone and I started to question what all the work was for. All the nights in the lab and work on the weekends… The confirmation that we were on the right track was no consolation. It took days for me to recover my motivation. What helped me a lot were my supervisor Professor Martin Bähler and my colleagues. They encouraged me. Even though some of the work had lost its novelty, we still had an interesting story that needed to be told. We subsequently worked hard to restructure and complete our story. It was really worth the effort and we were able to publish our myosin 19 story. This was one of the moments when I realised how important teamwork can be in science and I am grateful for all the positive energy and help I received!

“I realised how important teamwork can be in science…”

When doing the research, did you have a particular result or ‘eureka’ moment that has stuck with you?

In the last few years I did a lot of protein purifications. To get a protein recombinantly expressed and purified can be a long and challenging path. In cases where you want to perform binding assays, you need to purify at least two proteins. I invested a lot of time and effort to get both Miro and myosin 19 purified. The trick with the N- as well as C-terminally tagged myosin 19 was a great idea from my supervisor and helped me a lot. Also, the help we got from Sarah Rice's lab regarding Miro purification was very useful. It also showed me how valuable communication and exchange of information between different labs can be. At the end of the day, I not only managed to get both proteins purified but also saw a first positive result on my pull-down assay. I went to bed very pleased and slept extraordinarily well!

Electron micrograph of a cross-section of a HEK cell transfected with Mito–Apex II. Apex II catalyses diaminobenzidine into a spatially restricted precipitate that gives a high contrast after OsO4 treatment in electron microscopy. This staining method creates the illusion of mitochondria with zebra-like stripes and helps to visualise minute structures within cells.

Electron micrograph of a cross-section of a HEK cell transfected with Mito–Apex II. Apex II catalyses diaminobenzidine into a spatially restricted precipitate that gives a high contrast after OsO4 treatment in electron microscopy. This staining method creates the illusion of mitochondria with zebra-like stripes and helps to visualise minute structures within cells.

Oeding
,
S. J.
,
Majstrowicz
,
K.
,
Hu
,
X.-P.
,
Schwarz
,
V.
,
Freitag
,
A.
,
Honnert
,
U.
,
Nikolaus
,
P.
and
Bähler
,
M.
(
2018
).
Identification of Miro1 and Miro2 as mitochondrial receptors for myosin XIX
.
J. Cell Sci.
131
,
jcs219469
.