Entries by Arif Ashraf

Cyclin-dependent kinase inhibitors ensure formation of one functional megaspore per ovule (PLOS Genet)

Usually the female germline starts with one MMC (megaspore mother cell) per ovule that becomes four megaspores through the process of meiosis. Out of these four, only one survives to produce a functional megaspore (FM); the other three undergo a degeneration process. The FM forms the embryo sac. In this study, Cao et al. took […]

Review: The root transition zone: A hot spot for signal crosstalk (TIPS) ($)

Plant roots are an excellent system to study the interactions between endogenous (phytohormones) and exogenous (abiotic stresses) stimuli. The root can be considered as three sections: the meristematic zone (where active cell division occurs), the transition zone (acting as a boundary between meristem and elongation zones), and the elongation and differentiation zone (where cells elongate […]

AUX1-mediated root hair auxin influx governs SCFTIR1/AFB-type Ca2+ signaling (Nature Comms)

The phytohormone auxin is transported in a polar fashion through PINs (PIN-FORMED) and PGPs (P–GLYCOPROTEIN) as auxin efflux carriers and AUX1 and LAXs (LIKE-AUX1) as influx carriers. Previous experiments from oat coleoptiles and corn root hairs indicate that one of quickest auxin responses is cell membrane depolarization. In this study, Dindas et al. used Arabidopsis root […]

AUXIN RESPONSE FACTOR3 regulates floral meristem determinacy by repressing cytokinin biosynthesis and signaling ($) (Plant Cell)

The cross-talk between cytokinin and auxin has been well established from different developmental perspective. In this article, Zhang et al. have explored the role of cytokinin and auxin cross-talk in floral meristem (FM) determinacy. The authors demonstrated that auxin induces the expression of ARF3 (AUXIN RESPONSE FACTOR3) and ARF3 regulates both cytokinin biosynthesis and signaling. […]

Photoperiodic control of seasonal growth is mediated by ABA acting on cell-cell communication ($) (Science)

Plant growth is regulated seasonally, but our knowledge is limited about how their growth is inhibited or re-initiated seasonally. Looking at hybrid aspen, in this article, Tylewicz et al. explored how seasonal cycles of growth and dormancy help perennial plants adapt during winter. In the long days of summer, FT1 (FLOWERING LOCUS T 1) is […]

Membrane protein MHZ3 stabilizes OsEIN2 in rice by interacting with its Nramp-like domain (PNAS)

Much of the ethylene biosynthesis and signaling pathway has been characterized from study of  the dicot Arabidopsis. In this study, Ma et al. have characterized the ethylene insensitive mutant mhz3 from rice. MHZ3 is a membrane protein localized to the endoplasmic reticulum that interacts with OsEIN2 (ETHYLENE INSENSITIVE2). OsEIN2 contains a Nramp-like membrane-spanning domain and […]

Regulation of Arabidopsis Brassinosteroid receptor BRI1 endocytosis and ubiquitination ($) (PNAS)

BRI1 (BRASSINOSTEROID INSENSITIVE1) is a plasma-membrane localized brassinosteroid (BR) receptor that is endocytosed to internal membranes following BR binding. In this study, Zhou, Liu et al. provide a mechanistic model of BRI1 endocytosis through ubiquitination. They identified two E3 ubiquitin ligases, PUB12 and PUB13, responsible for the ubiquitination of BRI1. Additionally, they showed through a […]

The auxin-regulated CrRLK1L kinase ERULUS controls cell wall composition during root hair tip growth ($) (Curr Biol)

Root hair outgrowth requires the plant hormone auxin and polarized tip growth and cell wall deposition. Schoenaers et al. showed that the plasma membrane-localized receptor-like kinase ERULUS (ERU) regulates tip growth in root hairs. ERU is regulated by auxin via ARF7 and ARF19 transcription factors, which directly bind to the promoter of ERU. The function […]

A computational framework for cortical microtubule dynamics in realistically shaped plant cells (PLOS Comp Biol)

Plant growth and development consist of highly organized cellular patterns and depend on the directional growth and orientation of cells. Understanding microtubule dynamics is key to deciphering the formation of cellular shape and growth direction. In this research, Chakrabortty  et al. employed analytical and computational modeling approaches to simulate microtubule dynamics. They used confocal images […]