The Y chromosome is necessary and sufficient for the production of testes, and the testis-determining gene product is called SRY (for sex-determining region of the Y chromosome)

TLS Online TPP Program

#Id: 9496

#Unit 6. System Physiology – Plant

TLS Online TPP Program

#Id: 9497

#Unit 6. System Physiology – Plant

HC toxin produced by the fungal pathogen Cochliobolus carbonum of maize (Zea mays) inhibits histone deacetylase activity.

TLS Online TPP Program

#Id: 9498

#Unit 6. System Physiology – Plant

HC toxin is a cyclic peptide. It is synthesized continuously

by two specific tetrapartite cyclic peptide synthetases

(HTS1 and HTS2) and then exported outside the fungal cell. 

TLS Online TPP Program

#Id: 9499

#Unit 6. System Physiology – Plant

In maize (Zea mays) leaves, the HC toxin inhibits histone deacetylases to effect changes in host gene expression, presumably those genes involved in defense against C. carbonum.

TLS Online TPP Program

#Id: 9500

#Unit 6. System Physiology – Plant

Maize genotypes that carry the Hm1 gene, which encodes an enzyme that can metabolize and thereby detoxify HC toxin are resistant to C. carbonum.

TLS Online TPP Program

#Id: 9501

#Unit 6. System Physiology – Plant

Alternaria alternata f. sp. lycopersici produces the AAL toxin,

which activates a plant cell death program in tomato (Solanum

lycopersicum) leaves.