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An allelic resolution gene atlas for tetraploid potato provides insights into tuberization and stress resilience.

Tubers are modified underground stems that enable asexual, clonal reproduction and serve as a mechanism for overwintering and avoidance of herbivory. Potato (Solanum tuberosum L.) is cultivated for its tubers, which serve as a major crop. Genes responsible for tuber initiation and disease resistance have been characterized in potato including StSP6A, a homolog of flowering time, that functions as a tuberigen, the equivalent of a florigen. To elucidate additional molecular and genetic mechanisms underlying potato biology including tuber initiation, tuber development, and stress responses, we generated a developmental and abiotic/biotic-stress gene expression atlas from 34 tissues and treatments of the tetraploid potato cultivar, Atlantic. Using the haplotype-phased tetraploid Atlantic genome assembly and expression abundances of 129 218 genes, we constructed gene coexpression modules that represent networks associated with distinct developmental stages as well as stress responses. Functional annotations were given to modules and used to identify genes involved in tuberization and stress resilience. Structural variation from a pan-genomic analysis across four cultivated potato genome assemblies as well as domestication and wild introgression data allowed for deeper insights into the modules to identify key genes involved in tuberization and stress responses. This study underscores the importance of transcriptional regulation in tuberization and provides a comprehensive framework for future research on potato development and improvement.

Solanum tuberosum

An allelic resolution gene atlas for tetraploid potato provides insights into tuberization and stress resilience.

Tubers are modified underground stems that enable asexual, clonal reproduction and serve as a mechanism for overwintering and avoidance of herbivory. Tubers are wide-spread across angiosperms with some species such as Solanum tuberosum L. (potato) serving as a vital crop for human consumption. Genes responsible for tuber initiation and disease resistance have been characterized in potato including StSP6A, a homolog of Flowering Time, that functions as tuberigen, the equivalent of florigen. To elucidate additional molecular and genetic mechanisms underlying potato biology including tuber initiation, tuber development, and stress responses, we generated a developmental and abiotic/biotic-stress gene expression atlas from 34 tissues and treatments of Atlantic, a tetraploid cultivar. Using the haplotype-phased tetraploid Atlantic genome assembly and expression abundances of 129,218 genes, we constructed gene coexpression modules that represent networks associated with distinct developmental stages as well as stress responses. Functional annotations were given to modules and used to identify genes involved in tuberization and stress resilience. Structural variation from a pan-genomic analysis across four cultivated potato genome assemblies as well as domestication and wild introgression data allowed for deeper insights into the modules to identify key genes involved in tuberization and stress responses. This study underscores the importance of transcriptional regulation in tuberization and provides a comprehensive framework for future research on potato development and improvement.

Journal Article

Tuberous sclerosis. Comparison of computed tomography and conventional neuroradiology.

Sixty-two patients with tuberous sclerosis were studied by skull radiography. In addition, 16 had CT scanning, 26 had air studies, and 5 had cerebral angiography. Both subependymal and parenchymal tubers were shown on CT; all had a higher density than the brain and none were enhanced by contrast material. CT showed tubers in 13 of 16 patients, including 4 of 6 patients with glioma and hydrocephalus. Air studies showed subependymal tubers in 12 of 26 patients. Four other patients had intraventricular gliomas but no tubers. Skull radiographs showed spotty calcification, compatible with tuberous sclerosis, in 30 cases. Four patients had calcification compatible with tumor. Angiograms were nonspecific, showing intraventricular masses but no tubers.

Air

Ecological Filtering by Tuber Compartments Shapes Stable Core Microbiomes That Underpin Potato Plant Growth Across Environments.

Harnessing plant microbiomes for sustainable agriculture requires understanding not only whether they can boost crop performance, but also how ecological processes govern their assembly, stability, and functional contributions across environments. While we previously showed that seed tuber microbiomes can predict potato vigour using machine learning, it remained unclear how ecological processes shape tuber microbiome stability and functionality across host genotypes, tuber compartments, soil types, and years. Here, we analyzed the national-scale dataset of 240 field-collected potato seedlots, spanning six genotypes, two soil types, and two growing years, with a focus on the spatially distinct heel and eye compartments of the potato tuber. By profiling over 1200 bacterial and fungal communities and linking microbiome composition to plant performance, we show that plant genotype and tuber compartment are the strongest determinants of microbial diversity and composition. Compartment-specific enrichment of functional traits revealed spatial partitioning of microbial functions, with organic compound conversion and nitrogen cycling dominant in the heel, and energy metabolism enriched in the eye. Applying a macroecological abundance-occupancy framework, we identified a stable core microbiome of bacterial and fungal taxa that persisted across all environments and years. These core members were more strongly associated with plant growth-related traits than non-core taxa, and core taxa in different tuber compartments showed distinct correlations with taxa of potential pathogenic relevance. Together, our findings demonstrate that tuber compartments act as ecological filters that structure persistent, functionally specialised microbiomes linked to plant growth-related traits across environments. By providing an ecological and functional framework for compartment-resolved, stable core microbiomes, this study advances mechanistic understanding of plant-microbe interactions and identifies stable microbial partners as promising targets for improving potato resilience and productivity.

Journal Article

Natural plant enzyme inhibitors. VI. Studies on trypsin inhibitors of Colocasia antiquorum tubers.

A trypsin inhibitor was purified from the tubers of Colocasia antiquorum. The inhibitor acted on bovine trypsin, human trypsin and weakly on bovine chymotrypsin. The inhibitor, which had a molecular weight of 40 000, contained trace amounts of carbohydrates. The purified inhibitor was stable over a pH range of 2.0--12.0 and was more thermostable than the crude preparations. Trinitrobenzene sulphonate treatment resulted in the inactivation of the inhibitor. Chymotrypsin, pepsin and pronase digested the inhibitor. Pretreatment with trypsin at neutral pH resulted in the partial loss of antitryptic activity, whereas treatment at pH 3.7 led to complete inactivation. Evidence for the formation of a trypsin-inhibitor complex at pH 7.6 is provided. During the plant growth, in the early phase (0--40 days) there was a gradual increase in protein content and in antitryptic activity. The middle phase (40--55 days) was characterized by a rapid fall and abolition of the antitryptic activity and a diminution in protein content in the tubers. The immature tubers had low antitryptic activity compared to the mature ones. Mild heat treatment caused a sharp rise in antitryptic activity in the extracts of immature tubers but not with the mature tuber preparations.

Chymotrypsin

Renal failure secondary to angiomyolipoma. Case of Forme-Fruste tuberous sclerosis.

A fifty-four-year-old woman without the clinical features of tuberous sclerosis underwent nephrectomy at age thirty-three years for angiomyolipoma, and twenty-one years later severe renal failure developed. At necropsy the remaining kidney had extensive angiomyolipomatous involvement; not until the brain was examined was the diagnosis of tuberous sclerosis made. To date, this would appear to be the third case without clinical tuberous sclerosis in which renal involvement was the sole clinical expression of tuberous sclerosis, and the seventh reported instance of renal failure due to renal angiomyolipomatous hamartomatous transformation.

Female

[The correlation between autoregressive power spectrum of EEG and computerized tomography in tuberous sclerosis (author's transl)].

The autoregressive power spectrum and their component analyses of 36 electroencephalograms of 9 patients with tuberous sclerosis and 21 healthy children were studied. The data were recorded on the analog tapes, and the 20 second artifact free segment of records was digitized at 50 samples/sec. The autoregressive power spectrum and their component were calculated by the methods of Sato (1976) with the minicomputer PDP 11/40. The component consisted of the first and the second order elementary processes. The former showed a transient nonscillatory delta wave, whereas the latter showed damped oscillatory waves of delta, theta, alpha and beta rhythms in the EEG. The characteristics of these component rhythms in the EEG were given by the frequency, the time constant of the nonoscillatory delta, the damping time of the oscillatory component waves (time constant of the envelope of the damped oscillation), the mutual information amounts, etc. Thus, the correlation between these characteristics of component and CT-scan in tuberous sclerosis were examined. The results were as follows: 1. Compared with the characteristics of EEG in normal children, the mutual information amount, the damping time and/3r time constant showed significantly lower value in alpha rhythms of frontal-, central-regions and in theta, delta rhythms of occipital region in the patient with tuberous sclerosis. 2. Multiple subependymal high density areas were found in all of these patients on CT. EMI-number of these high density areas were less than that of calcification in younger children below the age of 3 years, but in older children were equivalent to that of calcification. 3. The correlation between the number of subependymal nodule on CT and the mutual information amount in the EEG showed significantly the negative coefficient in theta, delta rhythms of O1 region in older age group of patients. 4. The correlation between EMI-number of these subependymal high density areas and the mutual information amount in the EEG showed significantly thenegative coefficient in theta & delta rhythms of O1 region in all cases of patients. 5. It is considered that the multiple subependymal nodules may influence the background activities of the central and the occipital regions in the EEG of tuberous sclerosis.

Child

[Tuberous cortical irregularity at the distal femoral metaphysis--an often malignancy pretending radiological finding (author's transl)].

Four juvenile patients are described who were referred to us because of a tuberous, irregularly demarcated cortical lesion at the dorsal surface of the distal femur metaphysis suspected to be a "malignant tumor". The histologic evaluation in three of these patients revealed a fibroplastic reaction of the periosteum with periosteal new bone formation and focal, partly also lacunar bone resorption by osteoclasts. During six months of observation there were no signs of further growing. No therapy was necessary. This tuberous cortical defect at the dorsal surface of the distal femur metaphysis has been found almost exclusively in children and juvenile persons. As causative agent an increased muscle power of the gastrocnemius muscles has been discussed at the site of its bone insertion. If the bone formative component prevails a tuberous proliferation is evident radiographically, however, if the fibroplastic reaction is predominant there is more evidence for a cortical defect. The resemblance of the tuberous cortical defects in the four patients discussed here with those cases described in the literature under various names is pointed out.

Adolescent

Tuberous sclerosis and dysplasia of the corpus callosum. Case report of their combined occurrence in a newborn.

A neuropathological study is presented of a case showing the association of tuberous sclerosis of the brain and dysplasia of the corpus callosum as well as omphalocele and malrotated colon. No signs of tuberous sclerosis were found in the internal organs. From a review of the literature this appears to be the fourth case report of tuberous sclerosis and dysplasia of the corpus callosum. The association with omphalocele, to our knowledge, has not yet been reported.

Agenesis of Corpus Callosum

Tuberous sclerosis in old age.

A case of tuberous sclerosis without seizures in a 64-year-old man has been presented. Typical cutaneous, retinal, and bone lesions were found, along with calcifications in the lateral and third ventricle. Tuberous sclerosis is generally seen in young patients, though its occurrence in elderly patients has been described in the literature. Diagnosis in the present case was delayed. It is hoped that reemphasis of this aspect of tuberous sclerosis will lead to a prompt diagnosis in similar cases.

Age Factors

Tuberous sclerosis and Klippel-Trenaunay-Weber syndromes. Association of two complete phakomatoses in a single individual.

Tuberous sclerosis and Klippel-Trenaunay-Weber (KTW) syndromes are phakomatoses which are believed to be inherited separately. A 41 year old woman presented with the classic features of tuberous sclerosis: adenoma sebaceum, mental retardation, and seizures. In addition, the diagnostic triad of KTW involved the left lower limb: cutaneous naevi, a vascular anomaly, and osteohypertrophy. Arteriography documented the presence of visceral tumours and an arteriovenous malformation of the leg. This is the first reported association of the fully-developed symptomatology of tuberous sclerosis and KTW in one person.

Adult

The abdominal angiographic spectrum of tuberous sclerosis.

Tuberous sclerosis can present with a variety of clinical, roentgenographic and pathological manifestations. Although we are not advocating abdominal angiography in every patient with tuberous sclerosis, the clinical diagnosis may be difficult in certain cases, particularly in the young patient, and abdominal visceral angiography may lead to the correct diagnosis. In two of our patients, infants ten months of age, the diagnosis of tuberous sclerosis was not made until abdominal angiography had been performed. The most common changes are seen in the kidney where angiographic demonstration of hamartomas, arterial aneurysms, and multiple small cysts in the renal parenchyma are noted. Renal microcysts have not been previously described angiographically although they have been noted in pathological specimens and represent an important feature of the disorder spectrum. In addition, vascular hamartomatous lesions may be demonstrated angiographically in other abdominal organs such as the adrenal gland and liver.

Abdomen

Renal hamartoma (angiomyolipoma) and the tuberous sclerosis complex.

Renal hamartoma is found in 40 to 80 percent of patients with tuberous sclerosis. Microscopic demonstration of fat in the tissues of the mass is felt to be the most reliable diagnostic criterion of hamartoma.Characteristically, the angiographic appearance demonstrates a large, dilated feeding vessel passing through the mass with multiple, multisacculated aneurysmal dilatations appearing like bunches of grapes. There is a delicate neovascularity without A-V shunting and an onion-peel or whorl-like appearance in the venous phase.This case is presented to point out the close association of renal hamartoma and tuberous sclerosis and the need to search for renal hamartoma when the diagnosis of tuberous sclerosis is made.

Adenoma

Demyelination of the brain in tuberous sclerosis: computed tomography evidence.

Two patients with tuberous sclerosis are described in whom computed tomography of the head revealed areas of diffuse diminution of density suggestive of demyelination. Computed tomography is a sensitive test for the detection of intracerebral lesions in tuberous sclerosis, and the finding of areas of diminished density in the absence of evidence for tumor or ventricular obstruction correlates with the common histologic finding of diffuse demyelination. Serial studies with computed tomography are likely to determine whether such demyelination precedes the growth of hamartomas and calcification that characterize tuberous sclerosis.

Brain

Cytochrome c dependent, antimycin-A resistant respiration in mitochondria from potato tuber (Solanum tuberosum L.). Influence of wounding and storage time on outer membrane NADH-cytochrome-c-reductase.

Cytochrome c has two stimulatory effects on respiration of mitochondria especially those from wounded potato tuber. In the first place a stimulation of succinate- and NADH-consuming, antimycin-A-sensitive respiration, which reaches a maximal value at low cytochrome c concentrations, has been found. In the second place, at higher concentrations of cytochrome c a stimulation of NADH-consuming respiration occurs, which is antimycin-A-resistant, but KCN-sensitive. This antimycin-A-resistant, NADH-consuming respiration is absent, when no cytochrome c is added to the reaction medium. It is insensitive to metal chelators, to which the antimycin-A-and KCN-resistant plant mitochondrial alternative oxidase is sensitive. By measurements of NADH-cytochrome c reductase activities a corresponding antimycin-A-resistant NADH-cytochrome c reductase has been found, which is insensitive to osmotic shock treatment. A localization of this antimycin-A-resistant electron transport with NADH as the electron donor in the outer mitochondrial membrane is likely. In the mitochondrial preparations cytochrome c might stimulate by acting as an electron-carrier between the outer membrane reductase and the inner membrane cytochrome oxidase. A big increase of the outer membrane mediated electron transport in the mitochondria has been observed after wounding of potato tuber tissue. The ability of the tissue to produce this electron transport pathway after wounding disappeared after prolonged storage of the tubers. A possible function of this electron transport pathway in fatty acid desaturation during the wound-reaction is suggested.

Antimycin A

Preparation of high-fructose syrup from the tubers of the Jerusalem artichoke (Helianthus tuberosus L.

Fructose has recently received much attention due to renewed interest in natural sweeteners. In addition, fructose has some advantages to sucrose in sweetness, solubility, viscosity, and dental health characteristics. Fructose is deposited as storage fructans of the inulin (beta-1,2) type in tubers and rhizomes of the Compositae family. The utilization of the Jerusalem artichoke (Helianthus tuberosus) tuber as a source of fructose syrup is discussed. This plant has the potential to produce more sugar per acre than corn or sugar beets. In addition, the artichoke has higher frost resistance and lower heat unit requirements than corn and is somewhat more tolerant to low moisture conditions than sugar beets. A high quality fructose syrup can be produced from artichoke tubers. The extraction step was found to be particularly important since development of adverse colors and flavors must be prevented. The fructans may be acid or enzyme hydrolyzed but the latter method gave a higher quality syrup. Ion-exchange resins and activated charcoal were effective in removing coloring and flavoring materials, and also reduced other noncarbohydrate constituents. Since the enzymatic hydrolysis of the fructans is an attractive alternative to acid hydrolysis, a process was developed for producing and purifying a special beta-fructofuranosidase (inulase) from Saccharomyces fragilis. Inulase has a much higher specificity for fructans than commerically available beta-fructofuranosidase (invertase).

Carbohydrates

[Role of the digestive microflora and of the crystalline structure of starch in digestion and dietary efficiency in the chicken. Study of tropical tubers].

The influence of microflora in the utilization of starches, the X ray pattern which was of A or B type, was studied by balances and carcasses analysis with growing axenic or holoxenic chickens, put in isolators. Five tropical tubers were used : Manihot utilissima and Dioscorea dumetorum of A-type, Dioscorea cayenensis and alata and Canna edulis of B-type. They were introduced in isoenergetic (4,460 Kcal/g D.M.) and isoproteic (18 p. 100) diets. The A-type starches are entirely digested (95 p. 100) and the B-type are poorly digested (40-60 p. 100). The first ones induced a better growth than the second. The influence of digestive microflora changes with the two types of tubers used. With A-type starches the microflora lowered the feed intake, the growth and the energy and protein efficiency respectively--25 and--10 p. 100. When the diet included tubers with B-type starches, the low digestibility of starch and the low metabolisable energy in the diets induced poor growth and retentions. The results are discussed in relation with the starch breakdown into glucose, lactic acid and volatile fatty acids.

Animals

[Tuber avulsion from the forensic point of view].

On the basis of 6 case reports regarding avulsions of the tuber of the maxillary bone, the author comments on iatrogenic incidents in general. He deals in particular with the causes and the treatment of tuber avulsion and, finally, with forensiv aspects of this problem. He is of opinion that tuber avulsions are in most cases not due to malpraxis. The proper approach to the avoidance or the management of such a complication is explained.

Adult