Ching-Ho Chang

Ching-Ho

Background

Ching-Ho was born in Changhua, Taiwan. He went to the National Taiwan University for his Bachelor’s and Master’s degrees. There, he was first introduced to research using fruit flies as models under the mentorship of Dr. Chau-Ti Ting. The author finished doctoral studies in Biology at the University of Rochester in the lab of Dr. Amanda Larracuente. Ching-Ho is amazed by the diversity of chromosomes, and exciting to solve the many mysteries of chromosome evolution. He explored the hidden variation in regions of genomes constituted by repetitive sequences using genomics and cytology. He found that repetitive regions are extremely rapidly-evolving. Moreover, these regions might evolve new selfish meiotic drivers, which play by their own rules, can spread in populations—either by killing other sperm during male meiosis or segregating preferentially into eggs during female meiosis to bias their transmission. These selfish, repetitive sequences can jeopardize the benefits of the host, so we must deal with these repetitive lives. To see how organisms respond to these selfish meiotic drivers, he also studied the arms race between a meiotic driver (Segregation Distorter) and its suppressors in fruit flies using genetics. He found that Segregation Distorter can acquire multiple inversions that help it overcome a suppressor. Therefore, these inversions can maintain in nature despite carrying bad mutations, e.g., recessive lethals. Together, these results suggested that meiotic drivers play an important role in chromosome evolution.

Research Interests

“What's fair ain't necessarily right.” –Toni Morrison

The Mendelian First and Second Laws dictate that each allele from an individual will segregate equally to the next generation. These laws are held because each gamete from the same individual has the same chance to fertilize. However, gametes from the same individuals can have different genotypes; for example, in the heterogametic sex, gametes only carry one of the two sex chromosomes. Why should all gametes with different genotypes be transmitted equally? Ching-Ho’s postdoctoral research in the Malik Lab focus on how organisms ensure that their gametes can be fairly transmitted. He proposes that the rapid evolution of sperm chromatin might be responsible for silencing male meiotic drivers, which can kill other sperm to benefit themselves.

Publications

*Corresponding author, # Equal contribution

  1. Chakraborty, M.#, Chang, C.-H.#, Khost, D., Vedanayagam, J., Adrion, J. R., Liao, Y., Montooth, K. L., Meiklejohn, C. D., Larracuente, A. M.*, and Emerson, J. J.* (2020). Evolution of genome structure in the Drosophila simulans species complex. bioRxiv. doi.org/10.1101/2020.02.27.968743
  2. Chang, C.-H.#, Chavan, A. #, Palladino, J.#, Wei, X., Martins, N. M. C., Santinello, B., Chen, C. C., Erceg, J., Beliveau, B. J., Wu, C. T., Larracuente, A. M.*, and Mellone, B. G.* (2019). Islands of retroelements are major components of Drosophila centromeres. PLoS Biology, 17(5), e3000241. doi.org/10.1371/journal.pbio.3000241
  3. Chang, C.-H.*, and Larracuente, A. M.* (2019). Heterochromatin-Enriched Assemblies Reveal the Sequence and Organization of the Drosophila melanogaster Y Chromosome. Genetics, 211(1), 333-348. doi.org/10.1534/genetics.118.301765
  4. Courret, C.*, Chang, C.-H., Wei, K. H., Montchamp-Moreau, C., and Larracuente, A. M. (2019). Meiotic drive mechanisms: lessons from DrosophilaProc Biol Sci, 286(1913), 20191430. doi.org/10.1098/rspb.2019.1430 (Review)
  5. Lo, C.-W., Kryvalap, Y., Sheu, T.-j., Chang, C.-H., and Czyzyk, J.* (2019). Cellular proliferation in mouse and human pancreatic islets is regulated by serpin B13 inhibition and downstream targeting of E-cadherin by cathepsin L. Diabetologia, 62(5), 822-834. doi.org/10.1007/s00125-019-4834-0
  6. Fallon, T. R.#, Lower, S. E.#, Chang, C.-H., Bessho-Uehara, M., Martin, G. J., Bewick, A. J., Behringer, M., Debat, H. J., Wong, I., Day, J. C., Suvorov, A., Silva, C. J., Stanger-Hall, K. F., Hall, D. W., Schmitz, R. J., Nelson, D. R., Lewis, S. M., Shigenobu, S., Bybee, S. M., Larracuente, A. M., Oba, Y., and Weng, J. K.* (2018). Firefly genomes illuminate parallel origins of bioluminescence in beetles. Elife, 7, e36495. doi.org/10.7554/eLife.36495.001
  7. Chang, C.-H.*, and Larracuente, A. M. (2017). Genomic changes following the reversal of a Y chromosome to an autosome in Drosophila pseudoobscuraEvolution, 71(5), 1285-1296. doi.org/10.1111/evo.13229
  8. Martinson, E. O.* #, Mrinalini#, Kelkar, Y. D., Chang, C.-H., and Werren, J. H.* (2017). The Evolution of Venom by Co-option of Single-Copy Genes. Current Biology, 27(13), 2007-2013 e2008. doi.org/10.1016/j.cub.2017.05.032
  9. Chang, C. C.#, Ting, C. T. #, Chang, C.-H., Fang, S.*, and Chang, H.* (2014). The persistence of facultative parthenogenesis in Drosophila albomicansPLoS One, 9(11), e113275. doi.org/10.1371/journal.pone.0113275
  10. Cheng, C.-H. #, Chang, C.-H. #, and Chang, H.* (2011). Early-stage evolution of the neo-Y chromosome in Drosophila albomicansZoological Studies, 50, 338-349.

Background

Ching-Ho was born in Changhua, Taiwan. He went to the National Taiwan University for his Bachelor’s and Master’s degrees. There, he was first introduced to research using fruit flies as models under the mentorship of Dr. Chau-Ti Ting. The author finished doctoral studies in Biology at the University of Rochester in the lab of Dr. Amanda Larracuente. Ching-Ho is amazed by the diversity of chromosomes, and exciting to solve the many mysteries of chromosome evolution. He explored the hidden variation in regions of genomes constituted by repetitive sequences using genomics and cytology. He found that repetitive regions are extremely rapidly-evolving. Moreover, these regions might evolve new selfish meiotic drivers, which play by their own rules, can spread in populations—either by killing other sperm during male meiosis or segregating preferentially into eggs during female meiosis to bias their transmission. These selfish, repetitive sequences can jeopardize the benefits of the host, so we must deal with these repetitive lives. To see how organisms respond to these selfish meiotic drivers, he also studied the arms race between a meiotic driver (Segregation Distorter) and its suppressors in fruit flies using genetics. He found that Segregation Distorter can acquire multiple inversions that help it overcome a suppressor. Therefore, these inversions can maintain in nature despite carrying bad mutations, e.g., recessive lethals. Together, these results suggested that meiotic drivers play an important role in chromosome evolution.

Research Interests

“What's fair ain't necessarily right.” –Toni Morrison

The Mendelian First and Second Laws dictate that each allele from an individual will segregate equally to the next generation. These laws are held because each gamete from the same individual has the same chance to fertilize. However, gametes from the same individuals can have different genotypes; for example, in the heterogametic sex, gametes only carry one of the two sex chromosomes. Why should all gametes with different genotypes be transmitted equally? Ching-Ho’s postdoctoral research in the Malik Lab focus on how organisms ensure that their gametes can be fairly transmitted. He proposes that the rapid evolution of sperm chromatin might be responsible for silencing male meiotic drivers, which can kill other sperm to benefit themselves.

Publications

*Corresponding author, # Equal contribution

  1. Chakraborty, M.#, Chang, C.-H.#, Khost, D., Vedanayagam, J., Adrion, J. R., Liao, Y., Montooth, K. L., Meiklejohn, C. D., Larracuente, A. M.*, and Emerson, J. J.* (2020). Evolution of genome structure in the Drosophila simulans species complex. bioRxiv. doi.org/10.1101/2020.02.27.968743
  2. Chang, C.-H.#, Chavan, A. #, Palladino, J.#, Wei, X., Martins, N. M. C., Santinello, B., Chen, C. C., Erceg, J., Beliveau, B. J., Wu, C. T., Larracuente, A. M.*, and Mellone, B. G.* (2019). Islands of retroelements are major components of Drosophila centromeres. PLoS Biology, 17(5), e3000241. doi.org/10.1371/journal.pbio.3000241
  3. Chang, C.-H.*, and Larracuente, A. M.* (2019). Heterochromatin-Enriched Assemblies Reveal the Sequence and Organization of the Drosophila melanogaster Y Chromosome. Genetics, 211(1), 333-348. doi.org/10.1534/genetics.118.301765
  4. Courret, C.*, Chang, C.-H., Wei, K. H., Montchamp-Moreau, C., and Larracuente, A. M. (2019). Meiotic drive mechanisms: lessons from DrosophilaProc Biol Sci, 286(1913), 20191430. doi.org/10.1098/rspb.2019.1430 (Review)
  5. Lo, C.-W., Kryvalap, Y., Sheu, T.-j., Chang, C.-H., and Czyzyk, J.* (2019). Cellular proliferation in mouse and human pancreatic islets is regulated by serpin B13 inhibition and downstream targeting of E-cadherin by cathepsin L. Diabetologia, 62(5), 822-834. doi.org/10.1007/s00125-019-4834-0
  6. Fallon, T. R.#, Lower, S. E.#, Chang, C.-H., Bessho-Uehara, M., Martin, G. J., Bewick, A. J., Behringer, M., Debat, H. J., Wong, I., Day, J. C., Suvorov, A., Silva, C. J., Stanger-Hall, K. F., Hall, D. W., Schmitz, R. J., Nelson, D. R., Lewis, S. M., Shigenobu, S., Bybee, S. M., Larracuente, A. M., Oba, Y., and Weng, J. K.* (2018). Firefly genomes illuminate parallel origins of bioluminescence in beetles. Elife, 7, e36495. doi.org/10.7554/eLife.36495.001
  7. Chang, C.-H.*, and Larracuente, A. M. (2017). Genomic changes following the reversal of a Y chromosome to an autosome in Drosophila pseudoobscuraEvolution, 71(5), 1285-1296. doi.org/10.1111/evo.13229
  8. Martinson, E. O.* #, Mrinalini#, Kelkar, Y. D., Chang, C.-H., and Werren, J. H.* (2017). The Evolution of Venom by Co-option of Single-Copy Genes. Current Biology, 27(13), 2007-2013 e2008. doi.org/10.1016/j.cub.2017.05.032
  9. Chang, C. C.#, Ting, C. T. #, Chang, C.-H., Fang, S.*, and Chang, H.* (2014). The persistence of facultative parthenogenesis in Drosophila albomicansPLoS One, 9(11), e113275. doi.org/10.1371/journal.pone.0113275
  10. Cheng, C.-H. #, Chang, C.-H. #, and Chang, H.* (2011). Early-stage evolution of the neo-Y chromosome in Drosophila albomicansZoological Studies, 50, 338-349.