Skip to main content
PMC home page
Genetics logoLink to Genetics
. 2004 Mar;166(3):1451–1461. doi: 10.1534/genetics.166.3.1451

The maize macrohairless1 locus specifically promotes leaf blade macrohair initiation and responds to factors regulating leaf identity.

Stephen P Moose 1, Nick Lauter 1, Shawn R Carlson 1
PMCID: PMC1470767  PMID: 15082562

Abstract

The leaf surfaces of almost all plant species possess specialized epidermal cell types that form hairs or trichomes. Maize leaves produce three distinct types of hairs, the most prominent being the macrohairs that serve as a marker for adult leaf identity and may contribute to insect resistance. This report describes the maize macrohairless1 (mhl1) locus, which promotes macrohair initiation specifically in the leaf blade. Each of seven recessive mhl1 mutant alleles significantly reduces or eliminates macrohairs in the leaf blade. The mhl1 mutations block macrohair initiation rather than interfering with macrohair morphogenesis. Genetic mapping placed mhl1 within bin 4 on chromosome 9. A second independently segregating locus was found to partially suppress the mhl1 mutant phenotype in certain genetic backgrounds. Macrohair density was observed to increase during early adult vegetative development and then progressively decline, suggesting macrohair initiation frequency is affected by factors that act throughout shoot development. Genetic analyses demonstrated that mhl1 acts in the same pathway but downstream of factors that either promote or repress adult leaf identity. Thus, mhl1 plays a key role in integrating developmental programs that regulate leaf identity during shoot development with those that specify macrohair initiation within the leaf blade.

Full Text

The Full Text of this article is available as a PDF (207.4 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Borevitz J. O., Xia Y., Blount J., Dixon R. A., Lamb C. Activation tagging identifies a conserved MYB regulator of phenylpropanoid biosynthesis. Plant Cell. 2000 Dec;12(12):2383–2394. doi: 10.1105/tpc.12.12.2383. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Chandler V. L., Radicella J. P., Robbins T. P., Chen J., Turks D. Two regulatory genes of the maize anthocyanin pathway are homologous: isolation of B utilizing R genomic sequences. Plant Cell. 1989 Dec;1(12):1175–1183. doi: 10.1105/tpc.1.12.1175. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Chien J. C., Sussex I. M. Differential regulation of trichome formation on the adaxial and abaxial leaf surfaces by gibberellins and photoperiod in Arabidopsis thaliana (L.) Heynh. Plant Physiol. 1996 Aug;111(4):1321–1328. doi: 10.1104/pp.111.4.1321. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Cone K. C., Cocciolone S. M., Burr F. A., Burr B. Maize anthocyanin regulatory gene pl is a duplicate of c1 that functions in the plant. Plant Cell. 1993 Dec;5(12):1795–1805. doi: 10.1105/tpc.5.12.1795. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Evans M. M., Passas H. J., Poethig R. S. Heterochronic effects of glossy15 mutations on epidermal cell identity in maize. Development. 1994 Jul;120(7):1971–1981. doi: 10.1242/dev.120.7.1971. [DOI] [PubMed] [Google Scholar]
  6. Larkin J. C., Young N., Prigge M., Marks M. D. The control of trichome spacing and number in Arabidopsis. Development. 1996 Mar;122(3):997–1005. doi: 10.1242/dev.122.3.997. [DOI] [PubMed] [Google Scholar]
  7. Moose S. P., Sisco P. H. Glossy15 Controls the Epidermal Juvenile-to-Adult Phase Transition in Maize. Plant Cell. 1994 Oct;6(10):1343–1355. doi: 10.1105/tpc.6.10.1343. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Moose S. P., Sisco P. H. Glossy15, an APETALA2-like gene from maize that regulates leaf epidermal cell identity. Genes Dev. 1996 Dec 1;10(23):3018–3027. doi: 10.1101/gad.10.23.3018. [DOI] [PubMed] [Google Scholar]
  9. Nelson Jennifer M., Lane Barbara, Freeling Michael. Expression of a mutant maize gene in the ventral leaf epidermis is sufficient to signal a switch of the leaf's dorsoventral axis. Development. 2002 Oct;129(19):4581–4589. doi: 10.1242/dev.129.19.4581. [DOI] [PubMed] [Google Scholar]
  10. Nesi N., Jond C., Debeaujon I., Caboche M., Lepiniec L. The Arabidopsis TT2 gene encodes an R2R3 MYB domain protein that acts as a key determinant for proanthocyanidin accumulation in developing seed. Plant Cell. 2001 Sep;13(9):2099–2114. doi: 10.1105/TPC.010098. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Oppenheimer D. G., Herman P. L., Sivakumaran S., Esch J., Marks M. D. A myb gene required for leaf trichome differentiation in Arabidopsis is expressed in stipules. Cell. 1991 Nov 1;67(3):483–493. doi: 10.1016/0092-8674(91)90523-2. [DOI] [PubMed] [Google Scholar]
  12. Payne C. T., Zhang F., Lloyd A. M. GL3 encodes a bHLH protein that regulates trichome development in arabidopsis through interaction with GL1 and TTG1. Genetics. 2000 Nov;156(3):1349–1362. doi: 10.1093/genetics/156.3.1349. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Perazza D, Vachon G, Herzog M. Gibberellins promote trichome formation by Up-regulating GLABROUS1 in arabidopsis . Plant Physiol. 1998 Jun;117(2):375–383. doi: 10.1104/pp.117.2.375. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Poethig R. S. Phase change and the regulation of shoot morphogenesis in plants. Science. 1990 Nov 16;250(4983):923–930. doi: 10.1126/science.250.4983.923. [DOI] [PubMed] [Google Scholar]
  15. Schellmann S., Schnittger A., Kirik V., Wada T., Okada K., Beermann A., Thumfahrt J., Jürgens G., Hülskamp M. TRIPTYCHON and CAPRICE mediate lateral inhibition during trichome and root hair patterning in Arabidopsis. EMBO J. 2002 Oct 1;21(19):5036–5046. doi: 10.1093/emboj/cdf524. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Selinger D. A., Chandler V. L. A mutation in the pale aleurone color1 gene identifies a novel regulator of the maize anthocyanin pathway. Plant Cell. 1999 Jan;11(1):5–14. doi: 10.1105/tpc.11.1.5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Spray C. R., Kobayashi M., Suzuki Y., Phinney B. O., Gaskin P., MacMillan J. The dwarf-1 (dt) Mutant of Zea mays blocks three steps in the gibberellin-biosynthetic pathway. Proc Natl Acad Sci U S A. 1996 Sep 17;93(19):10515–10518. doi: 10.1073/pnas.93.19.10515. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Szymanski D. B., Lloyd A. M., Marks M. D. Progress in the molecular genetic analysis of trichome initiation and morphogenesis in Arabidopsis. Trends Plant Sci. 2000 May;5(5):214–219. doi: 10.1016/s1360-1385(00)01597-1. [DOI] [PubMed] [Google Scholar]
  19. Telfer A., Bollman K. M., Poethig R. S. Phase change and the regulation of trichome distribution in Arabidopsis thaliana. Development. 1997 Feb;124(3):645–654. doi: 10.1242/dev.124.3.645. [DOI] [PubMed] [Google Scholar]
  20. Walker A. R., Davison P. A., Bolognesi-Winfield A. C., James C. M., Srinivasan N., Blundell T. L., Esch J. J., Marks M. D., Gray J. C. The TRANSPARENT TESTA GLABRA1 locus, which regulates trichome differentiation and anthocyanin biosynthesis in Arabidopsis, encodes a WD40 repeat protein. Plant Cell. 1999 Jul;11(7):1337–1350. doi: 10.1105/tpc.11.7.1337. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Genetics are provided here courtesy of Oxford University Press

RESOURCES