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Andrew McCubbin

Andrew McCubbin

Field of Study: Plant Breeding Systems
Title: Emeritus Professor
Degrees: PhD, Reading University, UK
Homepage: Homepage/Lab Web Site Link
Google Scholar:  Google Scholar
Office: 440B Abelson Hall
Phone: 509 335 7916
Fax: nan
Mailing Address: School of Biological Sciences
Washington State University
PO Box 644236
Pullman,WA 99164-4236


Research in our lab centers on the developmental processes and signaling events associated plant reproduction. Our main focus currently is on the heteromorphic self-incompatibility (HSI) system in Turnera species. HSI promotes out-breeding by combining a set of morphological characteristics that differ between mating types, with a physiological recognition system. In Turnera there are two floral mating types, which exhibit reciprocally positioned male and female organ, the anthers and stigma. Pollen number and size, and the size and shape of stigmatic and stylar cells also differ between morphs, and these characters act synergistically to promote out-crossing, whilst a biochemical recognition system prevents pollen from the same mating type effecting fertilization. HSI is controlled by a diallelic S-locus, the short style morph is determined by the dominant S allele being Ss in genotype and the long styled morph is homozygous recessive (ss).
Traditional genetic studies suggested that this S-locus is in fact a supergene – a number of tightly linked genes inherited as a single unit. Identification and characterization of the genes which make up the supergene has the potential to make a significant impact of our understanding of floral biology, not just in the functioning and evolution of HSI systems, but also in the regulation of floral morphology (cell size and shape) and male reproductive capacity (pollen number). We have combined transcriptomic approaches to identify genes that are differentially expressed in floral tissues of the two mating types, with identifying and sequencing genomic BAC clones linked to the S-locus to unravel the molecular basis of this breeding system.
This project offers an opportunity to study several key aspects of plant reproductive biology and promises to provide new insights into the evolution and control of plant breeding systems. In addition recent developments in the use of transgenic crops have led to concerns about the escape of transgenes into wild relatives. One way to address this problem would be to reproductively isolate crop species. Through our studies we hope to make a valuable contribution to achieving this goal.

Representative Publications:

  • Matzke, C.M., Shore, J.S., Neff, M.M. and McCubbin, A.G. (2020). The Turnera style S-locus gene TsBAHD possesses brassinosteroid-inactivating activity when expressed in Arabidopsis thaliana. Plants 9, 1566; doi:10.3390/plants9111566.
  • Henning, P.M., Shore, J.S. and McCubbin, A.G. (2020) Transcriptome and network analyses of Heterostyly in Turnera subulata provide mechanistic insights: Are S-loci a red-light for pistil elongation? Plants 9, 713; doi:10.3390/plants9060713.
  • Shore, J.S., Hamam, H.J., Chafe, P.D.J., Labonne, J.D.J., Henning P.M., and McCubbin, A.G. (2019) The long and short of the S-locus in Turnera (Passifloraceae). New Phytologist 224:1316-1329.
  • Scheible, N and McCubbin, A.G. (2019) Signaling in Pollen Tube Growth: Beyond the Tip of
    the Polarity Iceberg. Plants 28, 156; doi:10.3390/plants8060156.
  • McCubbin A. (2019) Heterostyle Breeding Systems. In: eLS. John Wiley & Sons, Ltd: Chichester. doi: 10.1002/9780470015902.a0027953.
  • Burrows, B. and McCubbin A. (2018) Examination of S-Locus Regulated Differential Expression in Primula vulgaris Floral Development. Plants 2018, 7(2), 38;
  • Burrows, B. and McCubbin A.G. (2018) Reproduction overview by phylogeny: Plant. Ch. 20609. Encyclopedia of Reproduction 2nd Edn Vol 6, Elsevier (invited review chapter).
    McCubbin A. (2017) Breeding barriers: Duplicate S genes form new barrier. Nature Plants, 26 June 2017 (invited “news and views” article).
  • Burrows, B. and McCubbin A.G. (2017). Sequencing the genomic regions flanking S-linked PvGLO sequences confirms the presence of two GLO loci, one of which lies adjacent to the style-length determinant gene CYP734A50. Plant Reprod. 2017 Mar;30(1):53-67. doi: 10.1007/s00497-017-0299-9.
  • Guo, F., Yoon G.M, and McCubbin, A.G. (2013) PiSCP1 and PiCDPK2 localize to peroxisomes and are involved in pollen tube growth in Petunia inflata. Plants 2, 72-86.
  • Guo F and McCubbin, A.G. (2012). The pollen specific R-SNARE/longin PiVAMP726 mediates fusion of endo- and exocytic compartments in pollen tube tip growth. J. Exp. Bot. 63: 3083-95.
  • McCubbin, A.G. (2008) Heteromorphic self-incompatibility in Primula: Twenty-first century tools promise to unravel a classic nineteenth century model system. In “Self-Incompatibility in Flowering Plants, evolution, diversity and mechanisms”. Ed. V. Franklin-Tong. Springer. Pp 286-308.
  • Hetrick, A. and McCubbin, A.G. (2007) Heteromorphy and Flower Development in Primula. International Journal of Plant Developmental Biology 1(1): 82-86.
  • Roalson E.H., McCubbin, A.G. and Whitkus, R. (2007) Chromosome Evolution in the Cyperales. Aliso 23: 62-71.
  • Yoon, G.M., Dowd, P.E., Gilroy, S. and McCubbin, A.G. (2006) Calcium-Dependent Protein Kinase isoforms have distinct functions in pollen tube growth, including regulating polarity. The Plant Cell 18: 867-878.