First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping researchers promote themselves alongside their papers. JingHui Cao is first author on ‘ Artificial tethering of constitutive centromere-associated network proteins induces CENP-A deposition without Knl2 in DT40 cells’, published in JCS. JingHui is a PhD student in the lab of Tatsuo Fukagawa at the Graduate School of Frontier Biosciences, Osaka, Japan, investigating the relationship between cancer and chromosomal instability (CIN).

JingHui Cao

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

The kinetochore has a crucial role in the process of sorting chromosomes during mitosis. Normally, it acts like a leader that directs a team of proteins to set up camp in a specific spot on the chromosome called the centromere. Using a special tethering technique, we discovered something interesting: we could make this team set up camp in places on the chromosome other than the centromere. We wanted to understand how two specific kinetochore proteins, called CENP-C and CENP-I, bring in another important player, called CENP-A, to join their team in a non-centromere spot. To figure this out, we experimented by temporarily removing specific team members. We found that when we used our special technique to bring in CENP-C or CENP-I to a chromosome spot that wasn't at the centromere, CENP-A joined the team even when another key team member, Knl2, was absent. When we brought in Knl2, CENP-A joined even when CENP-C was absent. Moreover, CENP-C teamed up with another protein called HJURP, and they worked together without needing Knl2. Based on these findings, we determined that CENP-C binds CENP-A by teaming up with HJURP to build this team of proteins. Our work suggests that CENP-C and CENP-I can recruit CENP-A without needing Knl2, and this helps us better understand how kinetochore protein recruitment works inside cells.

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

The CENP-C–HJURP pathway for incorporating CENP-A hasn't gained widespread acceptance in the kinetochore research field. By utilizing a straightforward artificial tethering system along with rapid protein knockout methods and additional biochemical assays, our study clearly elucidated the CENP-C–HJURP pathway for incorporating CENP-A, notably in situations where Knl2, a primary component in the widely acknowledged Knl2–HJURP pathway, was absent.

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

When I conducted tethering experiments with CENP-I to investigate CENP-A incorporation at ectopic chromosomal loci when Knl2 was knocked out, I made a surprising observation. Contrary to our initial expectations of halted CENP-A incorporation under Knl2 knockout, I found that not only did CENP-A consistently integrate into ectopic loci, but its incorporation was notably hyperactivated. This unforeseen surge in CENP-A incorporation implies the existence of an alternative pathway for CENP-A incorporation, operating independently of the Knl2–HJURP pathway.

The incorporation of CENP-A hinges on CENP-I tethering in the absence of Knl2. The location of the LacO array is marked by the orange arrow. Chromosome-Z is blue (DAPI), mScarlet-tagged CENP-A is red, EGFP and LacI double-tagged CENP-I is green.

The incorporation of CENP-A hinges on CENP-I tethering in the absence of Knl2. The location of the LacO array is marked by the orange arrow. Chromosome-Z is blue (DAPI), mScarlet-tagged CENP-A is red, EGFP and LacI double-tagged CENP-I is green.

Why did you choose Journal of Cell Science for your paper?

I previously came across a paper in Journal of Cell Science that employed a comparable ectopic tethering assay to explore CENP-A incorporation. This particular paper has been a significant reference for my own work, thus highlighting Journal of Cell Science as a valuable resource in this research field. Recognizing its contribution to the field, I aim for my publication to emulate the standards set by this journal and intend for my work to serve as a useful scientific reference for fellow researchers.

Have you had any significant mentors who have helped you beyond supervision in the lab? How was their guidance special?

An assistant professor in our lab has been an invaluable mentor to me. During our lab meetings, he consistently shares his scientific insights and logical reasoning, elaborating on even the smallest details. His approach to problem solving and his meticulous explanations have greatly influenced my own thinking process. Over time, I've found myself adopting a similar scientific and logical framework, a testament to the impact of his guidance on my approach to thinking about research.

What motivated you to pursue a career in science, and what have been the most interesting moments on the path that led you to where you are now?

Interest and curiosity have been the driving forces behind my pursuit of a career in science, and the most captivating moments that have shaped my journey are the discoveries I have made. This includes the realization that CENP-I tethering induces CENP-A incorporation independently of Knl2, which challenges the widely accepted understanding in this field. Notably, this discovery was personally driven by my hands-on experimentation and exploration.

Tell us something interesting about yourself that wouldn't be on your CV

Despite my enjoyment of fishing and regular weekend fishing outings, studying and residing in Japan hasn't altered my taste in food – I'm still not particularly fond of eating sashimi!

JingHui Cao’s contact details: Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan.

E-mail: caojinghuihz@gmail.com

Cao
,
J.
,
Hori
,
T.
,
Ariyoshi
,
M.
and
Fukagawa
,
T.
(
2024
).
Artificial tethering of constitutive centromere-associated network proteins induces CENP-A deposition without Knl2 in DT40 cells
.
J. Cell Sci.
137
,
jcs261639
.