Abstract Detail

Evolutionary Developmental Biology (Evo-Devo)

Ganger, Michael [1], Smith, Hannah [1], Girouard, Julia [1], Bahny, Beth [1], Ewing, Sarah [1].

Antheridiogen and abscisic acid influence conversion and ANI1 expression in the homosporous fern Ceratopteris richardii.

The gametophytes of the homosporous fern Ceratopteris richardii may develop into either hermaphrodites or males. A gibberellin-like hormone, antheridiogen, is secreted by hermaphrodites and influences undifferentiated spores to develop as males in a process called induction. The gene ANI1 (Antheridiogen-Induced 1) has been shown to be expressed during induction and is implicated as a gene important for male development. Without antheridiogen spores bias toward hermaphrodite development, however abscisic acid (ABA) has been shown to be able to block induction even in the presence of antheridiogen. Males require the continued presence of antheridiogen to remain male, but may convert to hermaphrodites with its removal. Conversion was explored in C. richardii to determine if ABA affects conversion and if expression of ANI1 changes with conversion. Three-week old males were exposed to different concentrations of 0μM, 1μM, 10μM, 100μM, and 300μM ABA. Conversion was more likely to occur and occurred more quickly in low concentrations of ABA relative to higher concentrations. ABA has been shown to block induction during early development, but it appears to inhibit conversion. In a separate experiment, three-week old males were transferred to either media lacking antheridiogen; media containing 50μM ABA; or kept with hermaphrodites. After 72 hours, RNA was extracted, exposed to DNase, and converted to cDNA. qRT-PCR was used to determine if ANI1 expression changed in response to treatment. ANI1 expression dropped significantly in males transferred to media lacking antheridiogen, but remained high in males transferred to ABA. These results suggest a role for ANI1 throughout the male’s lifespan and implicate ABA as a potential regulator of ANI1 expression.

Broader Impacts:

1 - GANNON UNIVERSITY, BIOLOGY #3032, 109 UNIVERSITY SQUARE, ERIE, PA, 16541-0001, USA

Keywords:
Ceratopteris
fern
gender determination
induction
conversion
qRT-PCR
antheridiogen
Abscisic acid.

Presentation Type: Oral Paper:Papers for Topics
Session: 42
Location: Jasperwood/Riverside Hilton
Date: Wednesday, July 31st, 2013
Time: 11:45 AM
Number: 42007
Abstract ID:796
Candidate for Awards:None