Reversal of an immunity associated plant cell death program by the growth regulator auxin

One form of plant immunity against pathogens involves a rapid host programmed cell death at the site of infection accompanied by resistance, termed the hypersensitive response (HR). Here it is shown that the HR programmed cell death program initiated by the bacterial type III secretion system dependent proteinaceous elicitor harpin from Erwinia amylovora can be reversed till very late in the process by the plant growth regulator auxin. Early inhibition or late reversal of this cell death program does not affect marker genes tightly correlated with local and systemic resistance. Cross-regulation between cell death programs and growth regulators is prevalent in different kingdoms. Thus, the concept that cell death program can be reversed till late provides a framework for further investigation of such phenomena, in addition to having utility in choosing better targets and strategies for treating mammalian and agricultural diseases

Brewing moonshine for Mathieu

We propose a moonshine for the sporadic Mathieu group M_12 that relates its conjugacy classes to various modular forms and Borcherds Kac-Moody Lie superalgebras.Comment: 21 pages; LaTeX; no figure

Anisotropic model of dark energy dominated universe with hybrid expansion law

The paper deals with the study of the dynamics of Universe within the framework of a spatially homogeneous Bianchi-V space-time filled with a perfect fluid composed of non-interacting matter and dynamical dark energy components. We determine the Bianchi-V space-time by considering hybrid expansion law (HEL) for the average scale factor that yields power-law and exponential-law cosmologies in its special cases. In the HEL cosmology, the Universe exhibits transition from deceleration to acceleration. We find that the HEL Universe within the framework of Bianchi-V space-time is anisotropic at the early stages of evolution and becomes isotropic at late times. The dynamical dark energy in the HEL Bianchi-V Universe does not show departure from the usual cosmological constant at later times.Comment: 6 pages, 2 figures, 1 table; major revision done to obtain more general results; matches the version to be published in Gravitation and Cosmolog