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1.
Bishop Rosie R. Kubiak-Martens Lucy Warren Graeme M. Church Mike J. 《Vegetation History and Archaeobotany》2023,32(1):65-83
Vegetation History and Archaeobotany - This paper presents new evidence for the harvesting of edible plant roots and tubers at Northton, a Mesolithic hunter-gatherer site on Harris, in the Western... 相似文献
2.
Lucyna Kubiak-Martens 《Vegetation History and Archaeobotany》1999,8(1-2):117-127
Tybrind Vig is a late Mesolithic (Ertebølle) coastal settlement, dated to the period 5600–4000 BC. The site has yielded some very important finds associated with fishing activity, probably the best preserved example from the Mesolithic in Europe. Recently analysed botanical samples from submerged cultural deposits have provided evidence for the contribution of plants to the subsistence diet of the inhabitants of Tybrind Vig. The food plant remains are represented by the charred fragments of parenchymatous tissue from roots ofBeta vulgaris ssp.maritima (sea beet), fragments ofQuercus sp. parenchyma (acorn), and shell fragments ofCorylus avellana (hazelnut). The possibility that the grains ofGlyceria fluitans (floating sweet grass) and stems ofPhragmites australis (reed) were collected for food should not be excluded. In addition to the species identified in the charred remains, an abundance of edible plant seeds and fruits were represented in the waterlogged remains, suggesting that a much broader range of food plants was available in the area. These additional foods could have included a large variety of wild berries and other fruits, such asRubus idaeus, R. caesius, Fragaria vesca, Malus sylvestris, Cornus sanguinea, Crataegus monogyna/laevigata, Sorbus aucuparia, Viburnum opulus andRosa spp. Several other plants could have been gathered as green vegetables (Rumex crispus, Urtica dioica andCakile maritima), or could have been utilized for both their greens and seeds (Chenopodium album, Atriplex andScirpus maritimus). 相似文献
3.
Michèle M. Wollstonecroft 《Vegetation History and Archaeobotany》2002,11(1-2):61-70
Palaeoethnobotanical analysis of Late Period contexts (860±60 uncal B.P. to 160±50 uncal B.P.) at the site of EeRb 140, indicates
that it probably served as a seasonal work area, utilised during the mid to late summer by the residents of an adjacent pit-house
winter village. Food processing was evidently the primary plant-related activity at this open-air hunter-gatherer-fisher site
on the British Columbia Plateau in Canada. One feature appears to have functioned as both an open hearth for the drying and
preservation of berries and as a pit-oven, possibly for preparing foods for immediate consumption. Comparisons of the archaeobotany
of EeRb 140 with Plateau ethnographies suggest that women's task group activities are represented here. Most significantly,
the identification of a specialised plant-processing site in such close proximity to a winter village contrasts strongly with
existing ethnoarchaeological models for the British Columbia Plateau and introduces a type of site not previously identified
archaeologically in this region.
Received August 14, 2001 / Accepted March 13, 2002 相似文献
4.
Inactivation of DNA replication origins by the cell cycle regulator, trigonelline, in root meristems of Lactuca sativa 总被引:4,自引:0,他引:4
The effects of trigonelline (TRG) on the cell cycle in root meristems of Lactuca sativa L. were examined in the knowledge that TRG is a cell cycle regulator that causes cell arrest in G2, and prevents ligation
of replicons in S-phase. The hypothesis was tested that continuous exposure to TRG would perturb DNA replication which, in
turn, would lengthen the cell cycle and impair root elongation. Using DNA fibre autoradiography, mean replicon size was 31
and 13 μm in the TRG (3 mM) and control treatments, respectively. Trigonelline also resulted in a lengthening of both S-phase
and the cell cycle and a decrease in primary root elongation. Hence, replicon inactivation was responsible for the protracted
S-phase. Trigonelline treatment also resulted in a 1.6-fold increase in fork rate (13.8 μm h−1) compared with the control (8.4 m h−1). The faster fork rate in the larger replicons is in accord with the highly significant positive relationship already established
between fork rate and replicon size for various unrelated higher plants.
Received: 11 October 1999 / Accepted: 23 December 1999 相似文献
5.
In many types of plant cell, bundles of actin filaments (AFs) are generally involved in cytoplasmic streaming and the organization
of transvacuolar strands. Actin cross-linking proteins are believed to arrange AFs into the bundles. In root hair cells of
Hydrocharis dubia (Blume) Baker, a 135-kDa polypeptide cross-reacted with an antiserum against a 135-kDa actin-bundling protein (135-ABP),
a villin homologue, isolated from lily pollen tubes. Immunofluorescence microscopy revealed that the 135-kDa polypeptide co-localized
with AF bundles in the transvacuolar strand and in the sub-cortical region of the cells. Microinjection of antiserum against
135-ABP into living root hair cells induced the disappearance of the transvacuolar strand. Concomitantly, thick AF bundles
in the transvacuolar strand dispersed into thin bundles. In the root hair cells, AFs showed uniform polarity in the bundles,
which is consistent with the in-vitro activity of 135-ABP. These results suggest that villin is a factor responsible for bundling
AFs in root hair cells as well as in pollen tubes, and that it plays a key role in determining the direction of cytoplasmic
streaming in these cells.
Received: 16 September 1999 / Accepted: 3 December 1999 相似文献
6.
The town of Carquefou, some 10 km northeast of Nantes on the left bank of the river Erdre, occupies a site long associated
with human activity. During road construction east of the town, ditches, enclosures and post holes characteristic of the late
la Tène were discovered at the locality of “Le Clouet”, which led us to obtain core samples from a nearby peat bog. These
investigations indicated the changes in vegetation since 3915±95 uncal B.P., [2828 (2459) 2074 cal B.C.]. The slopes in the
surroundings of the bog have been relatively treeless since the Bronze Age, but a very open woodland vegetation composed of
Tilia, Corylus and Quercus has been maintained until the present day. In the area around the bog, and Alnus wood with an undergrowth of Cyperaceae was the dominant vegetation, despite some changes probably related to human occupation
since the Bronze Age. Beginning at 955±35 uncal B.P. [1004 (1036, 1144, 1146) 1181 cal A.D.], in the Middle Ages, the alders
disappeared almost totally, apparently because of clearance or an increase in water level. Human presence led to intensified
cultivation of different crops including Cannabis and especially Cerealia. Finally, the presence of a variety of anthropogenic indicator plants (Cichorioideae, Asteraceae,
Plantago lanceolata, etc.) suggests that cattle were reared in the vicinity of the site.
Received May 22, 2000 / Accepted March 29, 2001 相似文献
7.
Marjeta Jeraj 《Vegetation History and Archaeobotany》2002,11(4):277-288
Archaeobotanical evidence is presented for early agriculture at southwestern Ljubljansko barje (Ljubljana Moor), Slovenia.
Archaeobotanical finds from the Eneolithic site at Hočevarica, and pollen records from an archaeological profile and from
a nearby core were analysed. Numerous charred grains of cultivated cereals together with fossil seeds of Chenopodium sp. demonstrate that during the occupation of the settlement at Hočevarica, agriculture was well established. The majority
of identified grains were of Hordeum vulgare (cultivated barley) and the rest were Triticum monococcum and T. turgidum ssp. dicoccum (cultivated wheats). Large amounts of cereal pollen and pollen of Chenopodiaceae also suggest strong human impact on the
surrounding vegetation and landscape. Pollen and archaeobotanical data from Hočevarica show a large consistency in timing
of the appearance of agriculture. In the pollen record from the core at Hočevarica a significant increase (up to 40%) in cereal
pollen was detected at 4881 ± 50 B.P. (3770-3630 cal B.C.). Charred cereal grains were dated to 4800 ± 40 B.P. (3650-3520
cal B.C.). The grains of cultivated cereals from Hočevarica represent the oldest archaeobotanical evidence for agriculture
in central Slovenia.
Received February 18, 2002 / Accepted October 21, 2002 相似文献
8.
Summary. An assessment of the potential of proline to scavenge free radicals was made in a couple of in vitro assay systems, namely
graft co-polymerization and autooxidation of pyrogallol. Both these assays are essentially dependent upon free radical mechanisms.
Graft co-polymerization involved a ceric (Ce4+) ion- or γ-radiation-induced grafting of methyl acrylate (MA) onto a cellulose backbone. The degree of grafting, measured
gravimetrically, was taken as a measure of free radical generation. The γ-radiation-dependent grafting was far greater than
that due to Ce4+ ions. Inclusion of proline in the assay, irrespective of the initiator used, led to suppression of grafting in a concentration-dependent
manner indicating the ability of proline to scavenge free radicals. The γ-radiation-dependent grafting was also suppressed
by hydroquinone and glutathione but not by ascorbate, glycine and spermine. In contrast to graft co-polymerization, proline
did not inhibit the autooxidation of pyrogallol, a reaction involving superoxide radical generation. A subset of data constitutes
an evidence for the ability of proline to scavenge free radicals in vitro. It is implied by extension that free proline, known
to accumulate in plant tissues during abiotic stresses, would contribute to scavenging of surplus free radicals produced under
a variety of abiotic stresses.
Authors’ address: Shanti S. Sharma, Department of Biosciences, Himachal Pradesh University, Shimla 171 005, India 相似文献
9.
A cDNA encoding a novel inwardly rectifying potassium (K+
in) channel, LKT1, was cloned from a root-hair-specific cDNA library of tomato (Lycopersicon esculentum Mill.). The LKT1 mRNA was shown to be most strongly expressed in root hairs by Northern blot analysis. The LKT1 channel is a member of the
AKT family of K+
in channels previously identified in Arabidopsis thaliana (L.) Heynh. and potato (Solanum tuberosum L.). Moreover, LKT1 is closely related (97% identical amino acids) to potato SKT1. An electrophysiological comparison of
the two channels should therefore assist the identification of possible molecular bases for functional differences. For this
comparison, both channels were functionally expressed and electrophysiologically characterised within the same expression
system, i.e. Xenopus laevis oocytes. Voltage-clamp measurements identified LKT1 as a K+-selective inward rectifier which activates with slow kinetics upon hyperpolarising voltage pulses to potentials more negative
than −50 mV. The activation potential of LKT1 is shifted towards positive potentials with respect to SKT1 which might be due
to single amino acid exchanges in the rim of the channel's pore region or in the S4 domain. Like SKT1, LKT1 reversibly activated
upon shifting the external pH from 6.6 to 5.5, which indicates a physiological role for pH-dependent regulation of AKT-type
K+
in channels. The pharmacological inhibitor Cs+, applied externally, inhibited K+
in currents mediated by LKT1 and SKT1 half-maximally with a concentration (IC50) of 21 μM and 17 μM, respectively. In conclusion, LKT1 may serve as a low-affinity influx pathway for K+ into root hair cells. Comparison of homologous K+
in rectifiers from different plant species expressed in the same heterologous system allows conclusions to be drawn in respect
to structure-function relationships.
Received: 3 August 1999 / Accepted: 2 November 1999 相似文献
10.
Amy Bogaard 《Vegetation History and Archaeobotany》2002,11(1-2):155-168
Despite widespread criticism, the shifting cultivation model continues to inform discussion of Neolithic farming in Europe,
beginning with early Neolithic (Linearbandkeramik or LBK) communities concentrated in the loess belt of western-central Europe. Hundreds of LBK and later Neolithic sites have
been excavated in this region and many of them sampled for charred plant remains. Archaeobotanical data on the weed floras
harvested with crops provide the most direct archaeological evidence of crop husbandry practices, including the permanence
of crop fields, but have played a limited role in the debate over shifting cultivation. The Hambach Forest experiment, conducted
in the 1970s-80s near Cologne, Germany, provides valuable comparative data on the weed floras growing in newly cleared cultivation
plots in an area of longlived mixed oak woodland on loess-based soil. Correspondence analysis of the Hambach weed survey data
suggests that weed floras of fields managed under a shifting cultivation regime would be rich in perennial species, including
woodland perennials. Comparison of these results with Neolithic weed assemblages from the loess belt of western-central Europe
strongly suggests that Neolithic crop fields were not recently cleared of woodland vegetation but were long-established.
Received September 5, 2001 / Accepted February 26, 2002 相似文献
11.
Characterisation of extracellular polysaccharides from suspension cultures of members of the Poaceae
Microscopic examination of suspension- cultured cells of Phleum pratense L., Panicum miliaceum L., Phalarisaquatica L. and Oryza sativa L. showed that they were comprised of numerous root primordia. Polysaccharides secreted by these suspension cultures contained
glycosyl linkages consistent with the presence of high proportions of root mucilage-like polysaccharides. In contrast, suspension-cultured
cells of Hordeum vulgare L. contained mostly undifferentiated cells more typical of plant cells in suspension culture. The polysaccharides secreted
by H. vulgare cultures contained mostly linkages consistent with the presence of glucuronoarabinoxylan. The soluble polymers secreted by
cell-suspension cultures of Phleum pratense contained 70% carbohydrate, 14% protein and 6% inorganic material. The extracellular polysaccharides were separated into
four fractions by anion-exchange chromatography using a gradient of imidazole-HCl at pH 7.0. From glycosyl-linkage analyses,
five polysaccharides were identified: an arabinosylated xyloglucan (comprising 20% of the total polysaccharide), a glucomannan
(6%), a type-II arabinogalactan (an arabinogalactan-protein; 7%), an acidic xylan (3%), and a root-slime-like polysaccharide,
which contained features of type-II arabinogalactans and glucuronomannans (65%).
Received: 27 April 1999 / Accepted: 5 June 1999 相似文献
12.
Hypaphorine, the major indolic compound isolated from the ectomycorrhizal fungus Pisolithus tinctorius, controls the elongation rate of root hairs. At inhibitory concentrations (100 μM), hypaphorine induced a transitory swelling
of root hair tips of Eucalyptus globulus Labill. ssp. bicostata. When the polar tip growth resumed, a characteristic deformation was still visible on elongating hairs. At higher hypaphorine
concentrations (500 μM and greater), root hair elongation stopped, only 15 min after application. However, root hair initiation
from trichoblasts was not affected by hypaphorine. Hypaphorine activity could not be mimicked by related molecules such as
indole-3-acetic acid (IAA) or tryptophan. While IAA had no activity on root hair elongation, IAA was able to restore the tip
growth of root hairs following inhibition by hypaphorine. These results suggest that hypaphorine and endogenous IAA counteract
in controlling root hair elongation. During ectomycorrhiza development, the absence of root hairs might be due in part to
fungal release of molecules, such as hypaphorine, that inhibit the elongation of root hairs.
Received: 27 October 1999 / Accepted: 14 March 2000 相似文献
13.
First archaeological evidence of banana cultivation in central Africa during the third millennium before present 总被引:1,自引:0,他引:1
Christophe Mbida Mindzie Hughes Doutrelepont Luc Vrydaghs Rony L. Swennen Rudy J. Swennen Hans Beeckman Edmond de Langhe Pierre de Maret 《Vegetation History and Archaeobotany》2001,10(1):1-6
Phytoliths recovered from refuse pits excavated in central Cameroon and dated to ca 2500 B.P. have been positively identified
for the first time in Africa as derived from Musa the cultivated banana, after a comparative study of Musa and Ensete phytoliths. This discovery provides archaeologists with unequivocal proof of early agriculture in central Africa. Furthermore,
the presence of banana in Cameroon much earlier than previously assumed could explain how agriculture spread through the rain
forest. Lastly, as Musa is of Asian origin, this study provides the first concrete evidence of contacts across the Indian Ocean a millennium earlier
than currently accepted.
Received July 12, 1999 / Accepted May 4, 2000 相似文献
14.
Anne-Marie Lézine Jean-François Saliège Robert Mathieu Thibaut-Louis Tagliatela Sophie Mery Vincent Charpentier Serge Cleuziou 《Vegetation History and Archaeobotany》2002,11(3):221-232
Pollen and micropalaeontological analyses carried out on mangrove swamp sediments of Suwayh, Oman (22°05.589'N, 50°40.033'E)
reveal environmental changes linked both to climate (monsoon) and geomorphological (sea-level) variations during the Late
Holocene. A Rhizophora mangrove developed at Suwayh around 6000 years B. P. under climate conditions marked by an increased tropical influence as
compared to the modern situation, with dominant summer rains. The later extension of Prosopis cineraria at Suwayh provides evidence for a different rainfall pattern, with a winter rainy season. Pollen and micropalaeontological
composition shows three episodes influenced by the sea water at Suwayh. The most important corresponded to the mangrove episode
centred ca 6000 B. P. This was followed by two episodes of slight seawater incursion at ca. 5100 and 4500 B. P. responsible
for the formation of a brackish laagon. Comparison based on 14C measurements on shell recovered from both the sedimentary sequence of Suwayh and the nearby archaeological sites demonstrates
that close relations existed between man and mangroves during the Neolithic and the Early Bronze Age.
Received October 31, 2001 / Accepted January 24, 2002
Correspondence to: Anne-Marie Lézine 相似文献
15.
Summary. Our aim was to develop a liquid chromatography and electrospray ionization tandem mass spectrometry (LCMS2) method to measure free amino acid (FAA) and dipeptide (DP) concentrations in biological fluids. We synthesized chloroformate
derivatives of FAA and DP, identified the major precursor ions and used LCMS2 to obtain the most intense product ions. Using serial dilutions of unlabeled and labeled standards ([2H3]-L-Dopa, homoarginine, homophenylalanine, [15N]-Glutamine and [2H3]-methionine), we observed linear relationships in MS response that we used to calculate the amounts of FAA and DP in biological
samples. This method is sensitive with a limit of detection (LOD) for most of the FAAs and DPs tested in the 0.05–1 pmol range
and is linear over 3–5 orders of magnitude when many metabolites were measured simultaneously. Reproducibility and between
run or daily variations were <10% for most FAAs and DPs. We applied this method to human samples and quantitatively measured
21 FAAs and 2 DPs in 200 μl CSF, 31 FAAs and 6 DPs in 100 μl plasma, and 23 FAAs and 5 DPs in 200 μl urine. These data demonstrate
the potential for using LCMS2 to discover changes in FAA and DP metabolic pathways that occur during disease pathogenesis. 相似文献
16.
Summary. Glucocorticoid hormones enhance the reabsorptive capacity of filtered amino acids in rat kidney, as it was shown in previous
in vivo clearance experiments. In the present study, the site of glucocorticoid action on neutral amino acid transport in superficial
nephrons of rat kidney was investigated using in vivo micropuncture technique. Adult female Wistar rats were treated with dexamethasone (DEX), and fractional excretion of L-glutamine
(L-Gln) and L-leucine (L-Leu) were determined and related to inulin after microinfusion into different nephron segments. DEX
reduced fractional excretion of both neutral amino acids as a sign of enhanced reabsorptive capacity. The site of main DEX
action on L-Leu reabsorption has been localized in the proximal straight tubule. However, in the case of L-Gln, the inhibition
of γ-glutamyltranspeptidase (γ-GT) by administration of acivicin indicated the importance of this brush border enzyme in reduced L-Gln excretion. DEX enhanced
γ-GT activity by tubular acidification. It can be presumed a DEX-inducible transport system for neutral amino acids mainly
localized in proximal straight tubules of rat kidney.
Received July 8, 1999 相似文献
17.
Cloning and expression of UDP-glucose: flavonoid 7-O-glucosyltransferase from hairy root cultures of Scutellaria baicalensis 总被引:1,自引:0,他引:1
A cDNA encoding UDP-glucose: baicalein 7-O-glucosyltransferase (UBGT) was isolated from a cDNA library from hairy root cultures of Scutellaria baicalensis Georgi probed with a partial-length cDNA clone of a UDP-glucose: flavonoid 3-O-glucosyltransferase (UFGT) from grape (Vitis vinifera L.). The heterologous probe contained a glucosyltransferase consensus amino acid sequence which was also present in the Scutellaria cDNA clones. The complete nucleotide sequence of the 1688-bp cDNA insert was determined and the deduced amino acid sequences
are presented. The nucleotide sequence analysis of UBGT revealed an open reading frame encoding a polypeptide of 476 amino
acids with a calculated molecular mass of 53 094 Da. The reaction product for baicalein and UDP-glucose catalyzed by recombinant
UBGT in Escherichia coli was identified as authentic baicalein 7-O-glucoside using high-performance liquid chromatography and proton nuclear magnetic resonance spectroscopy. The enzyme activities
of recombinant UBGT expressed in E. coli were also detected towards flavonoids such as baicalein, wogonin, apigenin, scutellarein, 7,4′-dihydroxyflavone and kaempferol,
and phenolic compounds. The accumulation of UBGT mRNA in hairy roots was in response to wounding or salicylic acid treatments.
Received: 8 September 1999 / Accepted: 4 October 1999 相似文献
18.
Barbara Zach 《Vegetation History and Archaeobotany》2002,11(1-2):101-106
A sacred area was discovered in the centre of Mainz, the capital Mogontiacum of the Roman province of Upper Germany, Germania Superior. Recent epigraphical evidence led to the discovery that the temple had been dedicated to the goddesses of Isis and Magna
Mater. Sediments rich in archaeobotanical remains were recovered from more than 100 sacrificial pits for the burning of offerings,
15 large round sacrificial areas with stone walls, two favessae (coffers), several deposits under tiles on the floor, others on the floor itself, censers and other bowls, a well and a latrine.
The first results focus on the most conspicuous plant offerings, for instance considerable numbers of pine nuts and pine cones,
figs and dates. The aim is to establish an overview of the principal plants used as offerings and to determine the characteristic
features of typical offerings to Isis and Magna Mater. It was not expected that the assemblages would be so similar, regardless
of which site was analysed. Since no other sacred area from the Roman period has been as intensively investigated archaeobotanically,
the results are compared with others from the literature.
Received October 23, 2001 / Accepted May 7, 2002 相似文献
19.
Juan Carlos Berrío Arnoud Boom Pedro José Botero Luisa Fernanda Herrera Henry Hooghiemstra Freddy Romero Gustavo Sarmiento 《Vegetation History and Archaeobotany》2001,10(3):161-174
An environmental reconstruction of the last 10,000 14C years of a frequently flooded wetland ecosystem in the lower Magdalena valley in northern Colombia is presented, on the
basis of a multi-disciplinary study of the sediments of the upper 15 m of the core from Boquillas (74°33'E, 9°7'N; 20 m a.
s. l.). We used the following studies: pollen, lithology, organic structures, clay mineralogy, soil and sediment geochemistry,
and δ13C values. The chronology is based on 13 AMS radiocarbon dates; the humic acid fractions were used in the case of seven samples.
Pollen from local origin (swamps, open grass-rich vegetation, and gallery forest) show the development of the wetland area.
River-transported pollen from a greater distance (dry forest, montane forest, Alnus) show changes in river activity and reflect large-scale changes of climatic conditions in the Momposina basin. From c. 10,010
to 9370 uncal B. P. (zone BQS-Ia) the river system was of high energy, as inferred by the lithological changes. The landscape
was dominated by open grass-rich vegetation with gallery forest along the streams. A marked representation of Alnus and montane forest taxa indicate significant water transport and river dynamics. Climatic conditions were dry. From c. 9370-8430
uncal B. P. (zone BQS-Ib) wetlands were isolated from the main river system, and clayey sediments with kaolinite, smectite
and illite as the main minerals accumulated in a lower-energy environment. Climatic conditions were dry and changes in the
seasonal precipitation favoured the expansion of the gallery forest. From c. 8430 to 8040 uncal B. P. (zone BQS-Ic) low values
of river-transported pollen indicate dry climatic conditions and open vegetation became more abundant. The flooding frequency
of the Boquillas site diminished. From 8040 to 4900 uncal B. P. (zone BQS-Id) the Boquillas site was dominated by open vegetation
with patches of gallery forest along the streams. Supply of river-transported allochthonous pollen (from many sources) was
minimal. Clay minerals from the sediments suggest variable temperature and precipitation. From c. 4900 to 1550 uncal B. P.
)zone BQS-II) the site was within the reach of the main river system as is the case today. Frequent flooding, coinciding with
peaks of river-transported grains of Alnus and high sediment supply, point to high precipitation in the composite catchment area of the Magdalena, Cauca, San Jorge,
and Cesár rivers. High values of phosphorous in the upper part of the core point to the presence of a pre-Hispanic civilization,
approximately from 2000 uncal B. P. onward. Construction of an extensive drainage system allowed irrigation as well as drainage
depending the annual cycle of precipitation. The landscape was significantly modified and allowed an extensive crop production
on a system of raised fields.
Received May 18, 2001 / Accepted June 15, 2001 相似文献
20.
Alfin1 transcription factor overexpression enhances plant root growth under normal and saline conditions and improves salt tolerance in alfalfa 总被引:11,自引:0,他引:11
Plant root development is an essential determinant of plant growth and crop yield that could be enhanced by induced changes in the expression of root-specific regulatory factors. We reported previously that Alfin1 binds DNA in a sequence-specific manner and that Alfin1 overexpression in transgenic alfalfa (Medicago sativa L.) enhances expression of the salt-inducible MsPRP2 gene in roots, suggesting that Alfin1 functions to regulate gene expression in roots. Here we show that Alfin1 is an essential gene for root growth and that its overexpression in transgenic plants confers a many-fold increase in root growth under normal and saline conditions. Alfin1-binding sites occur in promoters of genes expressed in roots of a wide variety of plant species and we propose that it is a general root growth regulator. Even though Alfin1 overexpression was under the control of the CaMV 35S promoter, plant shoot growth was not adversely affected. We show further that introduction of the Alfin1 transgene in plants confers a dominant characteristic that significantly increases plant growth and salt tolerance. 相似文献