Functional redundancy

APP is a type-I transmembrane protein that is part of an evolutionarily conserved protein family, including the amyloid precursor-like proteins 1 (APLP1) and 2 (APLP2). APP and APLPs are functionally redundant and form homo- and hetero-oligomers. The absence of the A 3 sequence in the APLPs underlines the importance of APP that can only give rise to the A 3 species. Decreasing the formation of soluble A 3... 

MMPs for therapeutic interventions is complicated by the fact that MMPs are indispensable for normal development and physiology and by their multifunctionality, possible functional redundancy or contradiction, and context-dependent expression and activity. This complexity was revealed by previous efforts to inhibit MMP activity in the treatment of cancer patients that yielded unsatisfactory results. Doxycycline, at subantimicrobial doses, inhibits MMP activity, and has been used in various experimental systems for this purpose. It is used clinically for the treatment of... 

The most complex automated systems are used almost exclusively by centralized HTS operations in large pharmaceutical companies and are referred to as ultra HTS (uHTS) platforms. They typically consist of the same four functional instruments, but have the capacity to process several hundred plates per extended workday. They often incorporate a modular design philosophy with multiple duplicate instruments for enhanced capacity that offer some functional redundancy. The mechanism for moving plates from one instrument module to another is often, but not always, a continuous track-way that resembles an industrial assembly line rather than the robotic arm typically used in a workcell system [5-8],... 

The second cell-specific regulatory element within the distal enhancer is named SER. Loss of this element, which is at the extreme distal edge of the enhancer, leads to a selective loss of DDC expression in the ventral lateral serotonin cells (Johnson et al., 1989 Lundell and Hirsh, 1992) (Fig. 6C). This element has been delimited to about 40 bp and shows unexpected complexity, consisting of two functionally redundant elements. These two subelements, SERl and SERr, are each sufficient to allow normal DDC expression in the ventral lateral serotonin neurons if the other is deleted. In spite of this functional similarity, no sequence similarity is apparent between the two regions. The region of conservation between D. melanogaster and D. virilis is limited to SERl. 

Yin B, Crowley D, Sparovek G, De Melo WJ, Bomeman J (2000) Bacterial functional redundancy along a soil reclamation gradient. Appl Environ Microbiol 66 4361-4365... 

Inactivation of the tau gene by homologous recombination results in mice that are largely normal [22], indicating that tau is a nonessential protein. This may reflect functional redundancy. Thus, mice doubly deficient in tau and the microtubule-associated protein MAP IB exhibit nervous system defects that are more severe than those in the MAP IB single knockout line. 

Typically, process data are improved using spatial, or functional, redundancies in the process model. Measurements are spatially redundant if more than enough data exist to completely define the process model at any instant, that is, the system is overdetermined and requires a solution by least squares fitting. Similarly, data improvement can be performed using temporal redundancies. Measurements are temporally redundant if past measurement values are available and can be used for estimation purposes. Dynamic models composed of algebraic and differential equations provide both spatial and temporal redundancy. 

UBC5 148 [24] See UBC4 92% identical to Ubc4 functionally redundant [24]... 

In view of the conflict between the reliability and the cost of adding more hardware, it is sensible to attempt to use the dissimilar measured values together to cross check each other, rather than replicating each hardware individually. This is the concept of analytical i.e. functional) redundancy which uses redundant analytical (or functional) relationships between various measured variables of the monitored process e.g., inputs/outputs, out-puts/outputs and inputs/inputs). Figure 3 illustrates the hardware and analytical redundancy concepts. 

The presented approach has been applied on the process illustrated in Figure 8. In this case, several physical redundancy relations are available but the same method can be successfully applied with a standard instrumentation fulfilled by software sensors [17]. r, T2, rs, re, rr and ril are based on physical redundancy, r4 and rs on functional redundancy, rg, rg and riO are derived from dynamical modeling. As expressed in Table 2, there is not one single residual that is representative of a specific fault. A diagnosticability analysis of the signature table shows that among the 256 different states of the system ... 

A detailed analysis of ethylene receptor mutants has shown functional redundancy between them. However, in Arabidopsis, subfamily 1 members cannot be replaced by subfamily 2 members, in contrast to tomato in which functional redundancy between subfamily 1 and subfamily 2 members was reported. " " It seems that there exists some degree of plasticity among different plant species within the ethylene signaling pathway. 

More recently two functionally redundant Sfp-type PPTase, MxPptl and MxPptZ, have been found to differentially activate biosynthetic pathways in Myxococcus xanthus MxPptl and MxPptZ exhibit broad substrate specificity as supported by the fact that the complex PKS-NRPS hydrids epothilone and myxothiazol from Sorangium cellulosum and Stigmatella aurantiaca, respectively, could be expressed in M. xanthus without the need for an external PPTase. 

Sargent ML, Briggs WR, Woodward DO 1966 Circadian nature of a rhythm expressed by an invertaseless strain of Neurospora crassa. Plant Physiol 41 1343—1349 Selby CP, Thompson C, Schmitz TM, Van Gelder RN, Sancar A 2000 Functional redundancy of cryptochromes and classical photoreceptors for nonvisual ocular photoreception in mice. Proc Natl Acad Sci USA 97 14697-14702... 

Regulation of anthocyanin production involves transcriptional activators of the R2R3 MYB and the basic helix-loop-helix (bHLH) (or MYC) types (Table 3.2). This was first revealed by studies of the monocot Z. mays. It was found that the anthocyanin pathway is turned on in this species through the combined action of one member of the COLORED ALEURONEl (C1)/PURPLE PLANT (PL) MYB family and one member of the REDl (R)/BOOSTERl (B) bHLH family. The members of the MYB and bHLH families are functionally redundant, and their specific expression patterns enable spatial and temporal control of anthocyanin biosynthesis. 

Micheli, F. and Halpern, B.S. (2005) Low functional redundancy in coastal marine assemblages. Ecol Lett, 8, 391-400. 

J. H. (2003) Limited functional redundancy in high diversity systems resilience and ecosystem function on coral reefs. Ecol Lett, 6, 281-285. 

Rabin, R.S. Stewart, V. Either of two functionally redundant sensor proteins, NarX and NarQ, is sufficient for nitrate regulation in Escherichia coli K-12. Proc. Natl. Acad. Sci. USA, 89, 8419-8423 (1992)... 

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