Lewis J. Feldman | |
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Born | October 10, 1945 |
Nationality | American |
Alma mater | University of California, Davis (B.S., 1967) University of California, Davis (M.S.) |
Occupation | Professor of plant biology |
Employer | University of California, Berkeley |
Organization | Department of Plant & Microbial Biology |
Awards | Distinguished Teaching Award - UC Berkeley - 1996 |
Lewis Jeffrey Feldman (born October 10, 1945) is a professor of plant biology at the University of California, Berkeley, Director of the University of California Botanical Garden and previously Associate Dean for Academic Affairs in the College of Natural Resources. [1] He is in the Department of Plant and Microbial Biology. Feldman has taught at Berkeley since 1978. [2] He received Berkeley's Distinguished Teaching Award in 1996. [2] [3] Feldman's research focuses on regulation of development in meristems/stem cells, root gravitropism, and redox regulation of plant development.
After graduating in 1963 from Sunset High School in Hayward, California, Feldman attended the University of California, Davis, earning a B.S. in 1967, then an M.S., both in Botany. [2] He received a Ph.D. in biology from Harvard University in 1975. [1]
Feldman is a fellow of the California Academy of Sciences. [2] [4]
The hypothesis advanced here is that the signal transduction pathway for gravitaxis (gravitropism) evolved by building on and/or incorporating signal transduction steps which evolved earlier in connection with prokaryotes responding to light.(An abstract for a presentation)
John Gordon Torrey was a forthright, honest, highly principled man, and a groundbreaking plant scientist.
The Feldman Lab researches plant development e.g. how the populations of cells in and around the meristem interact to control root development.
A fellow of the California Academy of Sciences, Feldman's specialty is growth and development and root physiology. He received his BS and MS in botany from UC Davis and his PhD in biology from Harvard.
I delight in plants and I meet the challenge of drawing my students into the botanical kingdom as zealously as a missionary. I feel fortunate in my enthusiasm.
Lewis J. Feldman, Botany
1980 L.J. Feldman, University of California
1999 Lewis Feldman, Professor, Plant & Microbial Biology
Developmental biology is the study of the process by which animals and plants grow and develop. Developmental biology also encompasses the biology of regeneration, asexual reproduction, metamorphosis, and the growth and differentiation of stem cells in the adult organism.
In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the surface of the soil, but roots can also be aerial or aerating, that is, growing up above the ground or especially above water.
Phloem is the living tissue in vascular plants that transports the soluble organic compounds made during photosynthesis and known as photosynthates, in particular the sugar sucrose, to the rest of the plant. This transport process is called translocation. In trees, the phloem is the innermost layer of the bark, hence the name, derived from the Ancient Greek word φλοιός (phloiós), meaning "bark". The term was introduced by Carl Nägeli in 1858. Different types of phloem can be distinguished. The early phloem formed in the growth apices is called protophloem. Protophloem eventually becomes obliterated once it connects to the durable phloem in mature organs, the metaphloem. Further, secondary phloem is formed during the thickening of stem structures.
In cell biology, the meristem is a type of tissue found in plants. It consists of undifferentiated cells capable of cell division. Cells in the meristem can develop into all the other tissues and organs that occur in plants. These cells continue to divide until they become differentiated and lose the ability to divide.
Trichomes are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a plant is an indumentum, and the surface bearing them is said to be pubescent.
Auxins are a class of plant hormones with some morphogen-like characteristics. Auxins play a cardinal role in coordination of many growth and behavioral processes in plant life cycles and are essential for plant body development. The Dutch biologist Frits Warmolt Went first described auxins and their role in plant growth in the 1920s. Kenneth V. Thimann became the first to isolate one of these phytohormones and to determine its chemical structure as indole-3-acetic acid (IAA). Went and Thimann co-authored a book on plant hormones, Phytohormones, in 1937.
Gravitropism is a coordinated process of differential growth by a plant in response to gravity pulling on it. It also occurs in fungi. Gravity can be either "artificial gravity" or natural gravity. It is a general feature of all higher and many lower plants as well as other organisms. Charles Darwin was one of the first to scientifically document that roots show positive gravitropism and stems show negative gravitropism. That is, roots grow in the direction of gravitational pull and stems grow in the opposite direction. This behavior can be easily demonstrated with any potted plant. When laid onto its side, the growing parts of the stem begin to display negative gravitropism, growing upwards. Herbaceous (non-woody) stems are capable of a degree of actual bending, but most of the redirected movement occurs as a consequence of root or stem growth outside. The mechanism is based on the Cholodny–Went model which was proposed in 1927, and has since been modified. Although the model has been criticized and continues to be refined, it has largely stood the test of time.
Florigens are proteins capable of inducing flowering time in angiosperms. The prototypical florigen is encoded by the FT gene and its orthologs in Arabidopsis and other plants. Florigens are produced in the leaves, and act in the shoot apical meristem of buds and growing tips.
The ABC model of flower development is a scientific model of the process by which flowering plants produce a pattern of gene expression in meristems that leads to the appearance of an organ oriented towards sexual reproduction, a flower. There are three physiological developments that must occur in order for this to take place: firstly, the plant must pass from sexual immaturity into a sexually mature state ; secondly, the transformation of the apical meristem's function from a vegetative meristem into a floral meristem or inflorescence; and finally the growth of the flower's individual organs. The latter phase has been modelled using the ABC model, which aims to describe the biological basis of the process from the perspective of molecular and developmental genetics.
A primordium in embryology, is an organ or tissue in its earliest recognizable stage of development. Cells of the primordium are called primordial cells. A primordium is the simplest set of cells capable of triggering growth of the would-be organ and the initial foundation from which an organ is able to grow. In flowering plants, a floral primordium gives rise to a flower.
Lateral roots, emerging from the pericycle, extend horizontally from the primary root (radicle) and over time makeup the iconic branching pattern of root systems. They contribute to anchoring the plant securely into the soil, increasing water uptake, and facilitate the extraction of nutrients required for the growth and development of the plant. Lateral roots increase the surface area of a plant's root system and can be found in great abundance in several plant species. In some cases, lateral roots have been found to form symbiotic relationships with rhizobia (bacteria) and mycorrhizae (fungi) found in the soil, to further increase surface area and increase nutrient uptake.
Important structures in plant development are buds, shoots, roots, leaves, and flowers; plants produce these tissues and structures throughout their life from meristems located at the tips of organs, or between mature tissues. Thus, a living plant always has embryonic tissues. By contrast, an animal embryo will very early produce all of the body parts that it will ever have in its life. When the animal is born, it has all its body parts and from that point will only grow larger and more mature. However, both plants and animals pass through a phylotypic stage that evolved independently and that causes a developmental constraint limiting morphological diversification.
Peptide signaling plays a significant role in various aspects of plant growth and development and specific receptors for various peptides have been identified as being membrane-localized receptor kinases, the largest family of receptor-like molecules in plants. Signaling peptides include members of the following protein families.
Primary growth in plants is growth that takes place from the tips of roots or shoots. It leads to lengthening of roots and stems and sets the stage for organ formation. It is distinguished from secondary growth that leads to widening. Plant growth takes place in well defined plant locations. Specifically, the cell division and differentiation needed for growth occurs in specialized structures called meristems. These consist of undifferentiated cells capable of cell division. Cells in the meristem can develop into all the other tissues and organs that occur in plants. These cells continue to divide until they differentiate and then lose the ability to divide. Thus, the meristems produce all the cells used for plant growth and function.
Ling Meng is a Chinese plant biologist in the Department of Plant and Microbial Biology at the University of California, Berkeley. She is currently a Postdoctoral Fellow at Lawrence Berkeley National Laboratory. She is best known for discovering a novel form of cellular communication in plants. Thioredoxin, while known to play an important role in biological processes such as cellular redox, is not fully understood in function. Meng's work at Berkeley has suggested that thioredoxin h9 is associated with the plasma membrane and is capable of moving from cell to cell through two important protein post-translation modifications: myristoylation and palmitoylation. She is the first to connect thioredoxin with the plasma membrane.
In molecular biology mir-390 microRNA is a short RNA molecule. MicroRNAs function to regulate the expression levels of other genes by several mechanisms.
In molecular biology mir-396 microRNA is a short RNA molecule. MicroRNAs function to regulate the expression levels of other genes by several mechanisms.
CLE peptides are a group of peptides found in plants that are involved with cell signaling. Production is controlled by the CLE genes. Upon binding to a CLE peptide receptor in another cell, a chain reaction of events occurs, which can lead to various physiological and developmental processes. This signaling pathway is conserved in diverse land plants.
A cytokinin signaling and response regulator protein is a plant protein that is involved in a two step cytokinin signaling and response regulation pathway.
To assure that interaction, Feldman visits all 25 lab sections during the course of his five-week botany section.Feldman is quoted extensively in this article.
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Photo of Lewis J. Feldman |